I get what you're saying, but I just don't understand why anyone would give a shit about high school level football if you aren't a student there, or don't have a close relative playing. Different strokes for different folks. Enjoy sports however you like.
It's been like this for a long time in Texas (and I'm sure other places too). It's about town pride and support for the youth of your town. I don't have to know the kids on the team to want them to do well. You would also be surprised at how often you might know their fathers, or maybe they are an older or younger sibling to one of your kids friends. Maybe you coach youth sports and these are your former players. Maybe you are a business owner and their father/mother frequent your store. Maybe you have gone to church with those kids their whole life. There are a million ways you can find a connection to really want your high school to do well. In most of Texas, community is a very big thing. Especially rural Texas and the suburbs. If you live in one of the big cities it's probably closer to what you would see across of the rest of the nation. Just too many damn people for you to know who the hell is on the football team. As it is, while I might live somewhere else now, if I visit my hometown on a friday night during football season, you can bet I will make the game. You can also bet, despite me being gone for 15 years now, I will have some sort of family/friend connection to half those kids on the team. And will be damn proud of them win or lose. Even if you suck, playing football as a young man is pretty much what you do in Texas. At least until you can't make a roster anymore. It also opens so many doors for you in the community. It gets your name out there to the community. Might be stupid, but it is what it is. It shows work ethic, team work, and displays your desire to be the best by committing to something and giving it your all.
That's my really long winded serious post of the month.