I’ve posted a few times about concepts to introduce creative activities to a wider audience (check out the “Art theme night” tag for other examples). I’m not quite sure about the concept of combining restaurant dining and painting. The main upside to the restaurant seems to be increased drink sales. Mixing drinking with paint and inexperienced painters is just asking for someone to get their clothes ruined (I wonder who would be liable in such a case).
Having said that, I still think there is a germ of a good business idea in here. Having an audience watch some artists create pieces that are in line with a theme/concept paired with matching music would seem less problematic but is it entertaining enough?