emotion_hug sorry you have/had some nasty crews, the only thing I can suggest is putting them on ignore or make a note of their name and never crew with them again.
People will act like that due to the anonymity of the internet people can say mean things because you don't know who they are in real life.
The best suggestion for zOMG is when you random crew and you find a nice person friend them, post in forums and make friends so you can pester/ beg/blackmail them to join a crew with you. That way you get a better experience with zOMG by crew with people you like and get along with.