Family Frog Reunion?

Why is it family will say things that they would never EVER dream of saying to friends and casual acquaintances?

It seems that whenever my family gets together it is like a bunch of frogs sitting on their lilly pads just waiting for the opportune moment to ZING another one out there. It is almost like a sport and you'd think that their was trophy at stake from the pleasure that the zinger and surrounding audience get from the "zing" at the expense of the "zingee."

I'm curious: is it just my family or are other families like this too? Does my family just have a"zing" gene that enables them to whip out cleverly disguised criticisms and tear-downs left and right? Or perhaps it is a virus? Because those who marry into our clan appear to acquire the "gene" or the gift of "zing" too.

I am a sensitive person I know, but even outsiders that I bring to our family gatherings have commented on my family's (extended) gift for "zing". And IT/ZING bothers me! It makes me cringe at the thought of family get-togethers. And if I say anything: "I am being over sensitive ... people shouldn't have to walk on egg shells around me ..." etc., etc. Even my kids have commented on the word zapping: "Mommy, why does Aunt XXX or Uncle XXX say such mean things?"

I just wish people would stop and think before they open their mouths and let things fly-out.We tell our kids "If you don't have any thing nice to say: don't say anything at all." Doesn't that apply to adults too?

P.S. This 4th wasn't too bad with the exception of one sister who is under a lot of stress lately with a little one up all night. Is that an excuse? Guess so?