I know what you mean. In my experience, it just seems like many sub groups don't take criticism very well. They seem to follow one of the following:
1) We're doing this, not you. Your words are null. (i.e. LOOK AT OUR SUB CRED. WE DID THIS SHOW, SO YOU CAN FUCK OFF.)
2) No one will know the difference, and minor mistakes can go overlooked because we're doing this for free.
3) We don't have a place on staff for you.
Point 3 is the most understandable of the three, so I won't complain too much, but really, if someone is dropping the ball, tell him to get his shit together or replace him with someone who won't.
On that note, it bothers me that drama can even exist in the fansub community.