at the same time with you because they have stolen something, and you haven't. They check your receipt and you haven't stolen something. They check the honest people, and than the thieves get away. That's how that plan it. It has happened to me 3 times to me already when I have exited a store, and a stealer rings the thing, and goes out right when I'm exiting at the same time. Stuff like this is just sickening to me.
They really need to a) go after the people that steal stuff (I was in a store, and the people at the register just looked at the person that probably stole something because it went off, and they did nothing, but stared), and b) have longing exits. Don't put the metal detector right by the door. At the "new" Wal-Mart in Gurnee, they have it smart because they have that the metal detector is here, and than you have like maybe some 8 feet until you exit. They could get the people without walking out the door which is a great idea.