besides, you're playing a bar gig, and often the audiences aren't picky. i've seen bands i would never be a part of play, get people up and dancing and when each song was done, get enthusiastic applause. one local band had a 10+ residency at a very large bar, and they never improved - the drummer would mess up beats here and there, guitar would hit obvious wrong notes, bass player would speed up, the singer would come in late, but people loved them and would come out every week to see them. so i'd say that band fulfilled their main functions - they brought drinkers to the club, kept them happy and gave them a great time.
and isn't that at least a big part of the point?