Upvote:1
Let's say somebody traveled to USA from another country and immigration wanted to see proof of their ties to back home...
That's typically not the job of immigration but "ties back home" are most often formally assess during a Visa application.
Would the cost of the ticket play a factor in the border officer's decision to allow/refuse the alien entry?
Possibly. The may check the ticket to make sure you have a return flight (although that has never happened to me). If they do, that may see the fare class and it may affect their decision one way or the other.
US immigration officer have a depressingly large amount of discretion, so they can give you hard time for any or no reason at all (which has happened a lot to me). What these reasons might be and which way they move the needle is anyone's guess. They may not care, they may be jealous that you get to fly first and they do not, or they may feel that you are safe to enter since you got lots of discretionary income. Could go either way or no way at all.