Just a couple days ago, my daughters and I went to Walmart for some things. My older daughter was scanning items and scanned a greeting card, then passed the envelope past the scanner to put in the bag. The system stopped scanning and called for the worker. She played it back to see what was "wrong". It saw the envelope swiped past without scanning a SKU.The local Fry’s market now has overhead cameras on every self-check out station. They’re only 3’ above the station and not up high like in the rest of the store. Then or course they still have Nurse Ratchet standing nearby.