Unknown item in bagging area

[lethargic_man]

I was at the supermarket the other day, using the automated checkout. "Unknown item in bagging area," it complained, so I took the thing I'd most recently placed there off and put it back down. And again: "Unknown item in bagging area." Rinse, lather and repeat several times before my patience ran out and I summoned a staff member, who pointed out there was a small child perched on the end of the long, long bagging area.