There are a lot of good arguments in this thread so far and notice that most of them are IN FAVOR OF YOU NOT QUITTING! Don't do something so permanent as giving up on a sport you know you love and have invested so much in. Raven's and Madmorbius’ points I think are ideal: select the games you want to attend and avoid those people that are annoying. As a well recognized and respected “vet” you most probably get invited to more than enough private events to fill a season adequately so that you can usually skip on moron-filled games. Plus, there will always be less-than-ideal people that need to start somewhere, I'm sure I wasn't that great in my first year.
I noticed that I have been at it for a while and I'm sure that I had to deal with stupid people every season, yet I just remember the cool ones I met and the good moments in the games. Hence "the good old days" were probably pretty much the way things are now. There have been up-years and down-years too, years with a lot of players and years with a lot less, same for games and all. Maybe this is just one of those population volume up years.
On the whole, airsoft has always been THE sport for me, I have never really been disappointed, and remain unable to find anything else like it. I went through some mood changes about it too. Such as being worried? Yes. Annoyed? At times. Pissed? A couple of times. But never anything that would lead me to leave altogether. Actually, I find that the airsofting community is filled with people that are nicer than average and definitely more helpful. Eventhough we are all gun-totting, BDU-dressed weirdos.
Don't quit man, you are an amazingly respected and recognized member of a good community, I think your thread proves that, and veterans have a responsibility to help guide the remainder of the community. Whether actively or passively, that is a choice people can make and change as the mood dictates.