I saw four acts at the Bluesfest last night, but only have drawings of two. This is because I can't sketch or colour while I'm dancing.
I came up with an excellent improvement on my old schema with the festival chairs. I brought a padlock and a cable. When the Blues 'till Dusk stage became a dancing venue rather than a sitting venue, I folded up my flock of chairs and locked them to the fence. That way, we could all dance comfortably and I didn't have to worry about someone swiping the chairs.