Broadway, and its vicinity, sees some of the most unusual audience-cast interaction. My first gig out of college was playing bass in an off-Broadway musical ("Salvation", starring such unknowns as Bette Midler, Barry Bostwick, and Joe Morton). I played 6 nights a week, with an extra matinee show on two days, for about eight months. The show started with the band onstage and the cast in the audience. We'd be interrupted halfway through our "opening number" by the leading man, who then made his way onstage and called everybody else up (it was the end of the 60s...what can I tell you!).
The band quickly changed its hobby from seeing how smashed we could get and still play the book to watching the audience reactions. Once, an off-duty policeman, watching the show with his family, got up and began to arrest the leading man for "disrupting" the show. We had to intervene.
Another time, someone near the front row lit up a joint, to the chagrin of another audience member nearby. The fist fight that ensued nearly closed us down that night.
But, gee whiz, who among today's rock acts can top Sly and the Family Stone for showing up impeded? I went to a show at the Apollo where it took 45 minutes past curtain for the band to stagger out on stage, and I do mean stagger. The lady trumpet player could hardly stand up. Sly never even showed. But they managed to put on a show, and Larry Graham wailed, as usual.
(Originally posted on the pho list)