[petermcneeley]

RFID resolves this and other problems including inventory and theft. Even if you had to do this via visual inspection its still very possible.(http://mentalfloss.com/article/501060/man-buys-two-metric-to...)

[cwilkes]

I thought Walmart dictated to their suppliers that every item had to have an rfid chip in it, and this was years ago. Perhaps having one on every single item was cost prohibitive.