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.

So I posted the picture on my Facebook page asking if anyone who works at Hannaford knew what these were for. Plenty of people who didn't work at Hannaford chimed in claiming what I thought, that these were anti-theft devices, either to prevent stealing carts or making a noise when you leave the parking lot with them. Several claimed these devices lock up the wheels of the cart when it leaves the parking lot. That's a real technology, but it doesn't make sense when these are on grocery baskets with no wheels.

I got my answer from a reliable source. Brian Pietroski is a VIC Analyst at Ahold Delhaize, the company that owns Hannaford and Food Lion supermarkets in the United States as well as grocery stores all across the globe. "It tracks patterns of people in the store so we can see what their shopping habits are," Brian said in a comment. "They rolled it out down in the corporate office for Food Lion a few years ago. It helps with future designs of stores for a better customer experience and flow."

Now before you freak out thinking that Hannaford is tracking you personally, relax. According to Progressive Grocer, It's completely anonymous. Your phone knows way more about what you are doing than this device does.

You won't see these at all Hannaford Supermarkets, but if you do see them when you shop, now you will know what they are.

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