My DH is in a band as a hobby and they play bars and other music venues. Its not uncommon for the door person to ask attendees "what band are you here for?" The more 'ticks' the band gets, the better they get paid, some bars have a minimum draw the band must provide in order for the band to get paid at all (and some bars might even not let a band go on at all if they have no or too few ticks). He also does stand up comedy and again, he needs to provide a minimum number of paying audience members (who also have a 2 drink minimum once inside) in order to get to perform. If they require 8 audience members and he brings 7? Too bad, so sad, he doesn't get to go on stage.
So yeah, in the arts word its pretty common for artists to have to bear some responsibility for providing a paying audience.