What these sad-ass Tosh wanna-bes are doing is confrontational and deliberate. And yeah, if they're doing it in front of a group of their sad-ass buds, maybe it's not bullying but they're relying on strength in numbers.
Your comparison to drinking, driving fast, and hunting is dumb. I may drink too much, but I'm not picking fights or getting in a car and driving. I may drive over the limit, but not on a crowded highway. And when I hunt, I'm following safety guidelines. All these things are inherently dangerous, but I'm using common sense.
These guys are trying to pick a fight. Or...they're too damned stupid to realize they can jump up on someone with a dislocated shoulder or other injury and end up charged with assault. Or...as I said they're going to do it to the wrong guy and get their asses kicked. And, hey, it's all on video. Geniuses.
Get drunk off your ass, yell at other teams' fans all you want, but keep your hands off. Just common sense.