One idea I keep thinking about (which I'm sure interferes with some sort of copyright law) is: 1. User buys a physical copy of a movie/music 2. Instead of sending the disc to their house, it's sent to a storage facility 3. In the storage facility a digital backup is made and uploaded to a cloud storage 4. User is given access to the backup which they can watch/listen to 5. User would be the owner of said physical copy and when they sell it, all digital backups would be erased.

What's the legality that stops this from working?