"Perhaps it might be a nice idea to have folk in many non-pub venues, but you could have a problem getting many folkies there"

Myself, I'll go anywhere where there's music. When I'm sitting in a coffee bar I'll happily drink coffee, and I won't grumble if it doesn't sell beer. I'd be glad to have a chance to take part in a song or tune session in a bookshop, for example, and maybe I'd drop into a pub before and after. It's silly to limit in advance, in the way you imply, and wrong that the law should effectively force us to do so.