Theft is a bit more complicated sometimes. I think when someone or some organisation gets hold of the copyright of a record of some other person singing or playing and won't release it, and wont allow the person involved to release it either, as has happened often enough, that is a particularly nasty form of theft.
The same kind of thing arises when people succeed in enforcing a copyright restriction on something that should be public domain - taking into your private possession what belongs rightly to everyone is theft, and a very comfortable and profitable form of theft.