Do it. Put out a tip jar and see what happens. If it works out, see if you can get a standing date (every Friday, every other Saturday, the first Saturday of the month - you get the idea). People will begin to get used to you being there on that day and, before long, you could have a some regulars.

It's a situation that could benefit everyone - you get to perform regularly, the owner gets some business she might not have had, and the people in the community get an alternative to TV.

Good luck with it, Alex.