3. There's a proper sport culture
Sure, people are HUGELY into football (or, as you call it, "soccer") back home, but here, being a diehard sports fan doesn't always mean being a complete jackass. (Of course, there are exceptions). But where, in the UK, fans get into brawls when their teams lose (or win), American sports fans seem more jovial. For example, they enjoy lighting things on fire when their teams win championships.
Then again, I've admittedly never attended an SEC football game. That said, you have cheerleaders. People paint their faces to show team spirit. And at basketball games, the corny music I thought was only in movies is actually played. I can't imagine growing up in this country and not caring about any sport.