Mad Hot Ballroom copyright
Stay Free! has a great interview with Amy Sewell, writer and producer of the movie Mad Hot Ballroom, about the hell they had to go through to clear all the music in the movie:
If filmmakers have to worry about these things, documentaries will cease to be documentaries! What happens when the girls go shopping and there's music playing in the stores? We were lucky because in our movie the music wasn't identifiable, but otherwise what are we supposed to do: walk up to the store manager and say, "Excuse me but can you turn off your radio?"
I've been meaning to see this movie, I hadn't even thought of this aspect. Very interesting.