Kliph Nesteroff said this quote

The Mob essentially created the term 'stand-up comic'—according to eighty-six-year-old comedian Dick Curtis: 'The Outfit used to manage fighters. A stand-up fighter is a guy that is a puncher. A stand-up guy was a guy who was tough and you could depend on. The Outfit managed fighters and they managed clubs that booked comics, so the term found its way into the lexicon of nightclubs. A guy who just stood there and punched jokes—joke, joke, joke—he was a stand-up comic.