Fan Base Fascination
On the other side of that is what took place in Houston. When certain fans of the Texans actually were booing there own starting Quarterback for getting injured. Even the opposing team players took offense to that type of fan base passion and that is the monster.
Football is that one sport where the fans only get to see their team play 1 game per week for 16 weeks out of the year so the fervor of the buildup to game time is unlike any other Sport so it's understandable how the emotions run so high. With that said sometimes that emotion is taken a bit too far. The Fans mentality of "WE" did it can quickly turn to "YOU" suck and hope bad intentions come your way.
This fascination to me goes back generations and will continue with even more social media interaction for generations to come.