As to your original question, which country are you located in? This makes a difference as to what cellular data is available to you.
What school are you going to?
How old are you?
If you are in the US and are looking for an alternative provider you may get your wish in the future. In one of the most recent spectrum sales in the US, Google bought spectrum rights and have them available to develop an cellular network IF they wish to either put up cell towers or purchase space on existing towers. So you could by your data services from them in the future.
Spectrum sales are public so it is easy to check and find out that Apple has not participated in these auctions and owns no spectrum in the US. There were rumors they would do so but they did not. They could sign a contract with AT&T, Verizon, etc. to become an MVNO using their broadband but I think that is a remote idea. Too many competitors and they would be a cut-rate service. Not what Apple does.