Saw this on the news last night. When a call is received, they use video cameras to find the problem being reported, (you tell them where it's happening) and an officer is sent out to take care of it.
OP, you can't possibly defend the actions of some fans, just by saying :
"What the hell do people expect at a football game? Go catch a figure skating event if you can't handle it. "
Many fans are just stupid about this game, and cause trouble for anyone who dares wear any clothing that supports the visiting team. Look at Oakland fans...The "black hole" fans throw batteries and all kinds of crap at people. Many people get assaulted for wearing a ball cap of the opposing team. Remember the @sshole and the snowball incident a couple of years ago in Green Bay?
How can anyone excuse such behavior? It's a GAME, and is supposed to be fun for all to watch. Too many people in this country (and other countries as well) get way too worked up over watching millionaires play a silly game.