I just expect crazy comments & even bizarre behavior by the public at gigs, even in the nicest places. Once I played a few tunes at a friend's house--a former musician--on his Steinway M, at a party. Not a gig; Just 'cuz he & his wife like my playing, & I like to play, etc. Another guest glommed on to me & started telling me how to play, on & on with some weird semi-drunken bs. Next day my buddy calls me, pis*sed off b/c the other guest had gotten so weird, & I had to try to explain to him, that piano players expect this sort of stuff, it just rolled off.
Just sit down at the piano, & start to play, & it incites a certain # of people to start spewing their own agressive weirdness, at you. Someone told me once that a lot of them are "jealous".....
Then there's the endless stupid comments & questions that people make if you even TELL them you're a musician--so I generally don't.