1. Football (and mens basketball) are forced to pay more or less for the rest of all the other sports on campus[0]. Because of Title IX, student athletes/scholarships provided need to be equal across gender, which means that there need to be women's teams, which almost always lose money. You can make an argument that there shouldn't be other men's sports that lose money, but thats not what is being discussed.
2. Football/Collegiate sports in general are major drivers of diversity in colleges that are lacking in them. I've heard that at UC Berkeley that over half of black male students are athletes. Those are students that are very valuable for administrators trying to bring diversity to campuses.
3. Good football (and men's basketball) teams increase the rankings for the schools in general[1]. This has a demonstrable effect on student applications[2].
4. The culture around football games is that of partying. You go out, drink for a couple of hours before the game, and then stand in the sun for a couple of hours cheering for your team. They're fun when they're competitive, but Alabama was playing competition that was sub-par, so the games were out of hand by the end. Watching something exciting is fun. Watching something boring is not.
In my opinion, Nick Saban (Alabama's football coach) is probably the most underpaid state employee in the US.
[0]https://www.forbes.com/sites/sportsmoney/2011/05/05/does-foo...
[1]https://www.jstor.org/stable/27739784?seq=1#page_scan_tab_co...