Do you pull pranks at the grocery store?

I was chatting with this guy at the Walmart deli last month. His daughter standing aside quietly. I get to the cashier and notice a sandwich in my cart I didn't place thereto. I quickly put it together. I walked back to the deli and hold it out to the young lady.

Excuse me, I say, but you misplaced your sandwich, the shock of being confronted for her little joke leaving her gobsmacked. I laughed and put it back on the shelf.

Occasionally at Walmart, if I was passing the aisle where they hang all the letters for the side of your mailbox, I would grab a dozen and rehang them spelling words. Usually nothing too vulgar. Haha