Upvote:5
It is not particularly weird, although probably different from many countries.
The situation is similar in Canada where the border officer grants status upon entry and the validity of visa itself can be different (although nowadays most visas are granted for either 10 years or at least the duration of study/work).
First of all, the validity of visa here is not equivalent to the validity of the visa status.
The distinction between visa (entry authorization) and immigration status is made in a number of countries. Many countries (e.g. China, Japan, South Korea, Brazil, Iran) allow the duration of authorized stay to be different from the visa validity, e.g. you can enter on the last day of your visa validity and be admitted for more than one day.
In a number of countries (in particular many within EEA/Switzerland, also China and South Korea, and probably more), for certain situations, an alternative status document (residence permit) must be applied and obtained for a legal stay, although these documents can usually be used for entry as well.
Moreover, it is not possible to obtain/change the US visa while staying inside the country, yet it is possible to change the status.
Most countries above do allow visa application (or application for re-entry authorization) to be made within the country though. The impossibility to obtain an re-entry authorization inland might be somewhat exceptional for the U.S., someone else may have more knowledge or examples.