On occasion I've mentioned (jokingly with a smile) from the stage, only when people were disruptive, that playing here tonight is a bit like playing to a cage filled with gerbils & it sure would be nice it parents (or social workers) could try a bit harder to control their charges.I might even say good-naturedly "Hey good folks, if you could hold down the inappropriate sounds we'd all appreciate it." That way the rest of the audience would know I had them in mind too and not mind it too much when I'd shift gears and go into sing-alongs for the rest of my program. Things like "She'll Be Coming 'Round The Mountain" and "The Old Lady That Swallowed A Fly" where loud TOOT TOOTS might be apropriate.
In frustration I might even sing "The Boys Of Bedlam".
When ya get lemons, make lemonade.