I don't see why saying "athletes can be paid" should naturally lead to "all athletes MUST be paid". There is no reason you can't have a football program run as

I don't see why saying "athletes can be paid" should naturally lead to "all athletes MUST be paid". There is no reason you can't have a football program run as a separate entity with paid athletes and also have a school fencing program where athletes aren't paid and just play for fun and / or are on scholarship.