We have a guild on the Ebon Hawk who does that, they kicked my Merc friend for needing on a spec appropriate Aim piece, and they were the only aim user. It happens, try to remember their names and add them to ignore or something. Oh, and file a ticket...though I don't know what can be done.
Edit: If you want to know the guild, feel free to PM me, rather not start a forum war...
Im on the Same server and had a very similar incident with a particular guild
Also had some guys just talk so much trash that one guy quit and then kept up this whole l33t speak about how they can two man it and blah blah, I dropped and for like 10 mins got nasty messages in which I did not respond
A few scum bags out there but it's pretty rare still