True.
Nina Paley, the woman who made the excellent
Sita Sings the Blues, discovered that. She ended up crowd-funding the money to get a license so she could give the film away. Apparently it would have cost more in lawyers fees to renegotiate the standard contract than just go with the standard contract. Read the FAQ for more details.
Consider this a plug for the film, BTW. Excellent work, and the soundtrack was well worth the purchase price for me. (Free film, but Annette Hanshaw's songs are still in copyright so cost. Worth it — she had a great voice.) I rewatch this film every time one of my nieces gets dumped by a jerk boyfriend.
Asking is relatively easy. When Luthor Wright and the Wrongs asked Pink Floyd about recording a bluegrass version of The Wall, they got encouraged to do it. Sent them a sample song and got asked for the whole album. The result is pretty good: