The one thing that was strange was that gamestop almost always broke disks in half before throwing them out.

I think this is a common method to disincentivize people from taking stuff. Many moons ago I worked at Walmart and they did the same stuff in the claims area. They would damage everything to make it worthless and then either toss it in the trash compactor or send it back to the manufacturer. They damaged it to male sure that it couldn't be sold again and to somewhat prevent people from using this as a method to 'launder' good items that they'd come back later to take home.