Letting a Bull into a China Shop

One time, a friend invited me along to their support group meeting for people who have been traumatized by other people who take things to literally.  One of our mutual friends said that inviting me to this meeting was like letting a bull into a China shop.  I told our friend that he shouldn't make racial assumptions like that, since I'm sure there would be more than just Chinese people at the meeting, and that I also didn't appreciate being compared to a big, ugly, sweaty, bovine.  Some people don't make very good friends.