Oh they can do so much worse than that. Wait until the total is rung up and then begin the search for a check book, careful fill out the check asking for the correct amount at least 3 times. Then before tendering the check carry out all the bookkeeping on the stub. Tender check - ID - return to bottomless purse for wallet - find ID. All tasks complete, a light conversation with the checker about the trivia of the day.
Of course 10 of the 200 items have no bar code so it has to be called in, looked up, and reported back. This is all enhanced by the first day on the job checker. And, you have to pee like a sick mule.