Did you forget the first and biggest one?

All those athletic scholarships are paid for by the sports teams. It’s free money for the university. And the football team funds all the other sports, so a lot of football money goes to the university as tuition for an out-of-state soccer player or something.

Plus who do you think the sports teams pay rent and facilities fees to? The university who owns their facilities. The teams are non-profit so football has little incentive to save money.