depperm's answer is correct, but there is more detail available in Mormon scripture to provide context for why exactly the three kingdoms are so disparate in glory and blessings that striving for the highest one is well worth it. I wish to provide this context here.

This talk provides a good summary of the kingdoms of glory and even includes bulleted lists of the blessings each kingdom obtains or misses out on, and as such it is an answer to this question.

Most of the scriptures I quote will come from Doctrine & Covenants Section 76, which is the vision Joseph Smith received on the three kingdoms of glory and to this day provides the most detail on the subject of anything in Mormon canon. Because of this, I highly recommend anyone interested in the answer to this question read D&C 76. Unless otherwise indicated, any verse I reference in this answer will be a verse in D&C 76. Also, I may not provide a link to every single verse I reference in D&C 76. Also a note that my answer won't go into detail about what one must do to receive each kingdom; that's another question for another time, and is answered in the talk linked above.

The main thrust of depperm's answer and mine as well is that each of the three kingdoms has its own set of blessings that those who inherit that kingdom receive, and the differences between the sets of blessings are so large that striving for a higher kingdom over a lower is well worth the effort. This is stylized in the scriptures (both in D&C 76 and by Paul in 1 Corinthians 15) as comparing the glory of the sun, the moon, and the stars.

Blessings of the Celestial Kingdom, the glory of the sun

• Live in the presence of Heavenly Father and Jesus Christ (v. 62)
• Receive of the Father's fulness and glory (v. 56)
• Be priests of the Most High and be gods, even the sons of God (vv. 57-58)
• Overcome all things (v. 60)
• Come forth in the First Resurrection (i.e., be resurrected at the Second Coming of Christ if dead before Second Coming; be resurrected immediately after dying is dead after Second Coming) (vv. 64-65)

Additionally, in D&C 131 we learn that the Celestial Kingdom itself has three degrees within the kingdom, and that to obtain the highest one must enter in to the "new and everlasting covenant of marriage", i.e., a marriage that is sealed in the holy temple and whose participants fulfill the associated covenant. Those who obtain this highest degree aren't just saved in the Celestial Kingdom, they obtain exaltation and will be able to live the kind of life God lives. The set of blessings proclaimed on such couples (the language of the revelation indicates that these are blessings the sealed couples receive together) can be found in D&C 132:19-20 and include:

• "a continuation of the seeds forever and ever"
• "They shall be gods"
• "all things are subject unto them"
• "they have all power"

So that's what's available to those who inherit the Celestial Kingdom, which requires obedience to the commandments of God, including paying tithing and following the temple ceremonies.

Blessings of the Terrestrial Kingdom, the glory of the moon

This kingdom doesn't receive as much attention in D&C 76 as the Celestial and Telestial Kingdoms, so there's not as much to say.

• Receive of God's glory but not his fulness (v. 76)
• Receive the presence of the Son but not the fulness of the Father (v. 77)
• Do not receive the crown over the kingdom of God (v. 79)
• Receive ministering from Celestial beings (v. 87)
• Are able to minister to the Telestial kingdom (v. 86)

Blessings of the Telestial Kingdom, the glory of the stars

• Suffer the wrath of God on the earth (v. 104)
• Not resurrected until after the Millenium (v. 85)
• Not receive of Christ's fullness (v. 86)
• Receive the Holy Spirit through the ministering of the Terrestrial Kingdom (v. 86)
• "And they shall be servants of the Most High; but where God and Christ dwell they cannot come, worlds without end." (v.112)

Comparison

D&C 76 also records that the glory of the Telestial Kingdom "surpasses all understanding" (v.89), despite being the lowest kingdom. The Terrestrial Kingdom exceeds the Telestial Kingdom in all things (v. 91), and the Celestial Kingdom excels even beyond that in all things (v. 92). Thus, although there are blessings associated with membership in each kingdom, starting with a kingdom that surpasses all understanding and is associated with the glory of the stars, one can only imagine the immensity of blessings and happiness awaiting those who inherit the kingdom with glory like that of the sun.

Also relevant is this quote from Joseph Smith:

The great misery of departed spirits in the world of spirits, where they go after death, is to know that they come short of the glory that others enjoy and that they might have enjoyed themselves, and they are their own accusers.

(Quote and citation for the original source can be found in this chapter of this manual.)

In this comment, the OP said he was also wondering about the blessing of tithing and temple ceremonies in general. That would make this question border on asking three separate questions, but I'll give it a shot. (I'll only explain the blessings of tithing and temple ceremonies in particular, since the blessing of the celestial kingdom have been pretty well covered in the other answers).

Tithing

One of the blessing of tithing is that you get to materially contribute to the Kingdom of the Lord (PMG Lesson 4). The funds are used in a way directed by the Lord, so tithes are essentially owned by the Lord, which He uses to advance His work. Tithing are not used to pay Church leaders, most work in the Church is volunteer. (I think people like construction workers are paid. I'm not sure who else.) (A follow up question you might have is why people volunteer to do free service in the Church.)

Another blessing is that the Lord pour out His blessings. In Malachi 3:10-12 we read:

10 Bring ye all the tithes into the storehouse, that there may be meat in mine house, and prove me now herewith, saith the Lord of hosts, if I will not open you the windows of heaven, and pour you out a blessing, that there shall not be room enough to receive it.

11 And I will rebuke the devourer for your sakes, and he shall not destroy the fruits of your ground; neither shall your vine cast her fruit before the time in the field, saith the Lord of hosts.

12 And all nations shall call you blessed: for ye shall be a delightsome land, saith the Lord of hosts.

(see also 3 Nephi 24:10-12).

Indeed "faithful tithe payers learn that they cannot afford not to pay tithing" (True to the Faith). Some quotes from modern Church leaders illustrating the principle

During World War II, my widowed mother supported her three young children on a schoolteacher’s salary that was meager. When I became conscious that we went without some desirable things because we didn’t have enough money, I asked my mother why she paid so much of her salary as tithing. I have never forgotten her explanation: “Dallin, there might be some people who can get along without paying tithing, but we can’t. The Lord has chosen to take your father and leave me to raise you children. I cannot do that without the blessings of the Lord, and I obtain those blessings by paying an honest tithing. When I pay my tithing, I have the Lord’s promise that he will bless us, and we must have those blessings if we are to get along.” (Tithing by Elder Dallin H. Oaks, April 1994 General Conference)

After some events related to a civil war in Central America, my father’s business went bankrupt. He went from about 200 full-time employees to fewer than five sewing operators who worked as needed in the garage of our home. One day during those difficult times, I heard my parents discussing whether they should pay tithing or buy food for the children.

On Sunday, I followed my father to see what he was going to do. After our Church meetings, I saw him take an envelope and put his tithing in it. That was only part of the lesson. The question that remained for me was what we were going to eat.

Early Monday morning, some people knocked on our door. When I opened it, they asked for my father. I called for him, and when he arrived, the visitors told him about an urgent sewing order they needed as quickly as possible. They told him that the order was so urgent that they would pay for it in advance. That day I learned the principles of paying tithing and the blessings that follow. (The Language of the Gospel by Elder Valeri V. Cordón, April 2017 General Conference)

Another blessing of Tithing is that it prepares us for the ordinances in the temple.

Blessing of Temples

There are many blessings associated with the temple. One blessing that you receive from simply going to the temple is peace

As I think of temples, my thoughts turn to the many blessings we receive therein. As we enter through the doors of the temple, we leave behind us the distractions and confusion of the world. Inside this sacred sanctuary, we find beauty and order. There is rest for our souls and a respite from the cares of our lives. (Blessings of the Temple by President Thomas S. Monson, April 2015 General Conference).

You can also receive spiritual guidance (True to the Faith, Blessings from Attending the Temples).

The ordinances in the temples also give blessings. Also from True to the Faith, we read

One ordinance we receive in the temple is the endowment. The word endowment means “gift,” and the temple endowment truly is a gift from God. The ordinance consists of a series of instructions and includes covenants we make to live righteously and comply with the requirements of the gospel. The endowment helps us focus on the Savior, His role in our Heavenly Father’s plan, and our commitment to follow Him.

Another temple ordinance is celestial marriage, in which husband and wife are sealed to one another for eternity. A sealing performed in the temple continues forever if the husband and wife are faithful to the covenants they make.

Children born to parents who have been sealed in the temple are born in the covenant. These children automatically become part of an eternal family. Children who are not born in the covenant can also become part of an eternal family once their natural or adoptive parents have been sealed to one another. The ordinance of sealing children to parents is performed in the temple.

We can also perform ordinances on behalf of our ancestors, allowing them to receive the blessings associated with them.

This is a personal answer, but many of us really don't, how shall I put this? care to compete. We'll let God judge our efforts at the end.

But we still want to participate in the work of the Gospel, so we still obey the commandments, as we call them, the best we can. That includes supporting the Church with our tithing, and by participating in both the ordinary and the sacred aspects of church activity.