Before the Hells Angels were doing 24/7 surveillance on their precious sidewalk bench, they were presenting shows at the Anderson Theatre on 2nd Avenue. Where? The venue allegedly had around 5,000 seats (though some believe it was more like 2,000), and was originally a Yiddish Playhouse circa late 1800s or early 1900s. In the late '60s it became a rock venue, with Janis Joplin and Big Brother and the Holding Company had their New York debut (which took place on February 17, 1968).
Turns out Hilly Kristal also ran the CBGB Theater at the space from 1977-1978, which was christened by the Talking Heads. One local familiar with the joint says, "The place was disgusting. It made the CBGB club look like the Rainbow Room." The move to concert-sized venues was recognized by the NY Times, where the economic importance of such a move was noted.
You can get some more info and photos from EV Grieve, where it's pointed out that the Angels booked The Grateful Dead (and only charged a 2 buck donation).