For me music helps me concentrate with some tasks (especially in a more noisy environment where there are more distracting sounds), distracts for others, and for some just makes it a little less boring. I don't really find that I want it for the sake of displacing my own thoughts, if I'm bored doing something it's because there aren't any particularly interesting thoughts involved (and full disclosure, I have ADHD so my mind doesn't really need any encouragement at all to wander).