Being a professional musician (full-time and part-time) for almost 50 years, I have seen every type of gig imaginable. I've done gigs where I got paid over $1000 and other gigs where I paid them a few bucks thinking it was "good publicity" (hint: it rarely is). For the most part, local bars and restaurants run on a tight budget. If the venue has a full bar, they can afford to pay more than a restaurant with just a wine and beer license. What can you do?
A regular venue is stuck with the number of people they can seat. You can rearrange a few chairs and squeeze more people in but it's very limited. Enter ConcertWindow.com. They will broadcast your live video feed on the internet. You market not just the locals but your friends and family across the country and overseas. They view your performance online, chat about it on the same screen and leave a tip using the "Tip" button. The amount doesn't matter. The viewer determines how much to tip. Now you've got seats in the venue and a huge potential for income from the internet.
Now a venue, with some smart marketing, can build an audience of viewers online. The branding can be done based on the establishment or on the artists. Put them together and you got a powerful formula for success for both.