Whether some want to admit it or not, there is a line that shouldn't be crossed. I for 1 am appreciative of the noise being brought by the Diablos (the "kill" chant is growing and catching on throughout the arena), love the Baumann chant from my days growing up, and am happy that there is some sort of atmosphere at most games now. But the "Flyers swallows" part of the Rangers suck chant is beyond low class and has to stop.
As far as the other teams fans go, if they are respectful and just rooting for their team, then so be it. But if they come in to the Rock acting like an a$$, then give them hell for all I care so long as it doesn't get physical and profanities aren't thrown around every other word. You know, or should know, what you are getting into going into another teams arena and should act accordingly. Every time I've gone to MSG or the FU/WF Center wearing my Devils jersey, I root for the team and never make a comment back to anyone else. Usually those nit-wits have something stupid to say, but as long as you don't feed the beast, you'll be fine. I expect the same from visiting fans in our arena.