Oh, and the person who checks receipts isn't just casually looking. The person checking receipts randomly scans a few items in your cart and then scans your receipt and the computer tells them if anything they scanned in your cart is not on the receipt, so it's a legit check, and it's fast. The whole thing takes about 15 seconds per cart, and if there is a big line they have the option of just letting people go without getting checked, so I've never had to wait.