I can't claim I'm perfect and I have majorly put my foot in it. But I have also been where I have joked about my own group to have someone decide to make a point (in this case i know the person well enough to know the background) and make a public issue of how I cna't make the joke because it's not my group. Basically, he and my cousin (dad's side) informed me that my mom's side of the family didn't exist (get that one). Sort of the opposite to you, Kathy.
Humor and the rights to it can be used to divide in a lot of different ways. The funny thing is that the joke I told came from a Priest at my old grad school who never made the type of disinction that my cousin's husband did. Rather, he was simply glad that i made no Irish claims based on my dad's family's rather short - darned right hasty - stay in Belfast in the late 1600's enroute from Sutherland to Salem.
Kathy, I have to say that there are people in this world who's idiocy amaze me, and a fair number of them seem to have wandered into your life. But, yeah, I see enough of the same that I believe you, unfortunately. Wish the world was different. HUGGGSS all.