Copyright infringement occurs when you infringe on the (exclusive) right to copy, hence the name. Stealing DVDs doesn't create new copies, therefore it doesn't violate its copyright.
That's true in that case, but strictly it isn't quite true that any act that doesn't involve copying isn't restricted by copyright law.
E.g. in the EU, doing a public performance of a work is restricted by copyright, as is renting/lending to the public, though neither involves copying. (Don't ask me why someone thought it was a good idea to make copyright cover renting/lending, but there we are: http://goo.gl/WneMs ).
E.g. in the EU, doing a public performance of a work is restricted by copyright, as is renting/lending to the public, though neither involves copying. (Don't ask me why someone thought it was a good idea to make copyright cover renting/lending, but there we are: http://goo.gl/WneMs ).