I must confess, I have attended tournaments wearing the same t-shirt as many other players there. So I can totally relate to being one of the guys in the clique. If you have attended tournaments, you may have seen other people in my clique. I hope you have, and know immediately who we are.
You will know us by our dark blue "Fly Casual" shirts. Fly casual has been the mantra of the Xwing community to remind new and experienced players alike that this is a game. It is meant to be fun. If you're taking the game too seriously, you're probably playing the wrong game.
I have not seen the types of behavior described by the OP by this community. I have heard of these behaviors, and the locals are great about weeding those players out.
Fly Casual.