Ah but Georgian Silver, he doesn't need to open his bar for them AND pay extra staff. Sour grapes doesn't come into it. He was approached to do so. Now, surely, courtesy should prevail. Especially knowing that buying a sandwich or a coffee would have been a nice gesture and simply made it worth his while. I can see it now - "right, I'll attract their attention at the bar by jingling my bells excessively loudly whilst you sneak the tupperware and the thermos in to the corner and hide it under the table".
I think that anyone in their right mind that wants to 'make a killing' will steer well clear of the folk music scene. Let's face it, it really aint gonna happen!