I don't belong to a local guild, only our guild here. The few times I have taken classes at the LQS it seems most eveyone knows each other and is almost anti social to any new people. I never feel intimidated by this since I have dealt with all kinds of people in my professional life (retired college instructor). However, I can always sense at least a few new people are not comfortable. Also, a lot of time the class instructor is drawn in by the established students and others don't get questions answered and kind of just give up on doing anything in class. Hopefully, they have taken away enough instructions to try it at home.
I have heard people speak about guilds in the same way. Personally I get a lot more from the people on this board than any class I have ever gone to. So for me, sitting here looking at a totorial another board member has put together at my own speed is where I want to be. I'm sure there are great local guilds out there as well as great LQS classes: and if you find a fit you are lucky.