Irish, I wouldn't worry about it Some of those folks can be very petty sometimes...maybe it was a competitor of yours, who knows?
As far as the money orders go, you cannot advertise that you take them, but if someone asks, you are free to accept if you want to. There is a link from Ebay somewhere (I'll look for it) that says those very words. Remember, they want their final value fee, if it's by a money order so be it
BTW I once had a post removed for asking a question about another auction site...no biggie