A lot of times if I choose to join partys already in progress I'll run into that kind of situation. The person I'm backfilling for left for a GOOD REASON and a lot of times the reason is "omg I cannot deal with these people".

I sympathize, and remember the infamous words of George Carlin: "Think of how stupid the average person is, and realize half of them are stupider than that".

Bless you for backfilling.