I don't think it happens when its someones personal property but in a situation of a theatre or backline company who can absorb the cost of a mic. Probably a $100 SM58. I think it was Chris Rock who first did it at the end of a show and even with that it was a damn funny show.
What really gets me is recently guys trashing keyboards. Over on the Keyboard Corner forum there was a long discussion about a keyboard player throwing over a vintage Vox Continental and it was BORROWED !!! Owner wrote no real damage was done and he forgave him. Better man then me.
Recently on Saturday Night Live the player in the band first stood on and then threw over a Hammond B3. Some one posted it was an A100 in a beat up B case that belonged to the player. Still made the guy look like a total a**.
I go back to the days of the WHO trashing their instruments and its always made me mad. How many players (me included back then) would of loved to be able to get their hands on such gear.
The only story I like is Jerry Lee setting fire to a Baby Grand at a college show. He asked for an old beat up upright but they gave him the Baby Grand. Scene was featured in the movie "Great Balls of Fire"
He did write out a check for it after the show. I'll give him a pass, just because.