Me too - I see the word folk in the blurb, and a website with the heading "XXXX folk club" and, unlettered clod that I am, I make the silly assumption that it's a folk club.
Best to avoid 'em all like the plague, I think, lest I get buttonholed at the bar by anoraks muttering about 1954 (in my day that was just before eight).
Anyway, until such time as a decent folk club appears within 25 miles of my I'll stick to concerts (and our local theatre booker has excellent taste - we've had Bellowhead twice in the past two years, Eliza Carthy twice and June Tabor three times. I must work on her to extend the range a bit, though).