While TV grazing, I saw something that made me think.
During a broadcast of the Professional Bullrider's Tour, a profile was aired about one of the bulls. Accompanying the piece was Metallica's "Enter Sandman".
This same piece of music used to serve as the entrance theme for The Sandman, a professional wrestler best known for smashing his opponents with a bamboo cane and his own face with a beer can. He was one of the primary faces of ECW, a wrestling federation with mature storylines and sometimes shocking violence.
When the WWE purchased ECW, The Sandman's theme was replaced with generic guitar riffs, presumably to avoid royalties.
Just thinking out loud.