I just bought Metroid and now they want it back?

In walking out of the local GameStop and removing my copy of Metroid Prime 3 from its plastic bag prison, we noticed it felt kind of off when picking it up. That was because there is the large slip of paper you see above on the back. It's not enough that GameStop calls you during dinner asking for the game you bought from them back and even ruins the story to games while you're in the store, but now they're giving us trash to throw away when we buy games from them?

Maybe we're making too big a deal about a small slip of paper, but considering they have a monopoly in this town as far as release day games go, we're often forced to choke down their practices.