I hear this all of the time, it goes down like this:
It is a thread about some game, let's call it New Hotness and someone pipes in and says something to the tune of:
"I just bought New Hotness and really like it. I can't wait to play but will have to wait until a con or something because my group just won't go for it. I mean, one of my buddies is a fan of the novels that NH is based on and another friend of mine is up for anything but the other people in the group just hate the idea and love their characters in the ongoing campaign of Olde Hotness that has been going on for years."
So, why not just grab the two folks who are down with playing New Hotness, poke around among your friends and/or local games club and see if anyone else is down for trying something new, set up a game night and get playing? I don't think I'm inventing the wheel or discovering fire, here but this idea that we have one gaming group and must game with all of them just seems off to me.