They wait until everything is totaled, THEN they search for the checkbook hidden in a cavernous purse then commence to your scenario.
A couple of years ago I was in a checkout line and there was a fat guy in one of electric carts ahead. His basket was full and his wife also had a basket full.
When it came time to pay, he pulled out a huge roll of money from his pocket. ....Turns out there was over a hundred dollars in ONE DOLLAR bills! ...The poor cashier had to count the bills and make sure they were real.
I know $1 bills can build up, like pennies do, but why not just drop by the bank and get larger bills in exchange.
That grates on my nerves to no end.