Knuckle headed?

Barbados has launched the National Initiative for Service Excellence (NISE) and it can't take hold fast enough as far as many people are concerned, myself included. I had another example of how badly it's needed when I went to buy bottled water at the SuperCentre, at Rendezvous, a few days ago. With nothing else in my shopping cart but the bottles, I see on the register "Pork knuckle". "What's that?" I asked the cashier. She acted surprised and looked around to see where the knuckle was, and nothing remotely like a piece from a pig, raw or cooked, could be seen anywhere. "Sorry. I'm tired." she eventually replied. I counted as far as 3 then replied: "If you're tired, tell your boss and ask to take a rest. Don't go charging people for things they are not buying." A supervisor came over and adjusted the register, I paid and without any more discussion, left. When I mentioned this to some friends later in the week, they all laughed. "You catch her! She wanted to knuckle you for her dinner to take home later." I could understand that possible explanation of a form of petty pilfering. But wouldn't a smart person have tried to hide that knuckle-headed trick on a bill that had a few more items on it than bottled water? Maybe she wasn't smart and that's the problem. Or her eye sight was bad. Or she was finding a way of coping with the high cost of living. If you don't laugh, you have to cry.