To answer the question that started your post, yes I have performed at paid gigs. I was in a cover band way back in the day and we got a cut of the cover charge the bar collected at the door. This was after a few other gigs where we had to prove ourselves and most of that we did for free, or the band got paid in beer.
If you don't have a following or a reputation that you can perform I don't think you ask to get paid initially. If you have merchandise or original music to sell access to, I'm sure most places wouldn't care if you marketed those things to the audience. It would also help to ask all your friends and family to attend as well to fill the place up as much as you can. That was really the most important thing we did was getting all the band's friends to attend our shows. It helped that we played in a decent-sized college town and 2 band members were starters on the football team. It took a few months but we were able to fill up places and get some decent cash.
Thanks for listening to me brag about my younger music days
