From an RHUer:
By far, the strangest was a battery for a motorcycle. I had only been at Kroger for about a month, and was doing the morning pull of carts that had been left out all night. I noticed that a somewhat corroded motorcycle battery was sitting in one of the carts. Since I didn't want to burn my hands with acid, I alerted the manager, and he took the battery for recycling.
What's the strangest thing you've ever found in a shopping cart at work?