If you've shopped at the Hannaford Supermarket on Riverside Street in Portland lately, you may have seen new devices zip-tied to shopping carts and baskets. Most people assume these are anti-theft devices, but it turns out that's not the case. When I stopped in to pick up a few things last week, I grabbed a basket and saw a small, white box attached to the bottom of the grocery basket with a graphic of a shopping cart on it. I noticed they were attached to the front of grocery carts too. Townsquare Media - Jeff Parsons My first thought was that these were GPS devices to prevent people from leaving the store with shopping carts and baskets, a problem that retailers have been dealing with for years. Later I realized that if they were installed to prevent theft of the carts, all anyone would have to do is cut the zip tie, so that didn't make sense.