I have not gone to a group yet but honestly I'm more of a loner when it comes to my quilting and art in general.
That being said any time I've gone to LQS or a sewing machine shop I've been treated very nicely and respectfully. In fact once they see what I've done they are very encouraging.
I think some people are just rude and spiteful and just because you are a quilter doesn't mean you can't have those qualities.
Sorry that you have not found nice people.
Who knows I might be saying the same thing once I come back from my first quilting group meeting...
I should add that I'm 32 years old.