Excellent episode.
Mine happened in Morrisons years ago. I was sent to fetch a couple of bottles of Cola while my (ex) wife perused something else.
I duly went and retrieved said bottles and for some inexplicable reason I then held them up as pretend boobies and jumped around the corner of the aisle making machine gun noises a la femme bots from Austin Powers. (Expecting to surprise the missus).
Some old dear dropped her basket, screamed, almost fell over and half a dozen checkout lines fell into silence. Looking (glaring) at me.
And I had absolutely no comeback. I waved and walked over to the trolley, placed said bottles and joined the back of a disapproving queue.
One of those times.