Every football fan is different. Some are silent and studious, while others are boisterous or belligerent. Each is entitled to his own experience and to voice that opinion whenever he feels necessary.
However, is there a limit to the extent to which you express yourself? The question asked is how far is too far? Is it when someone is offended? What if there are children around? What about profanity? Is it too much if someone uses his first amendment right and uses some colorful language?
I myself am able to enjoy any sporting event, especially a football game, without ever having to use any sort of curse or profanity.