Sounds like your teller was an embezzler.
“Mistakes” of a few dollars every day can add up to thousands over time.
My pet peeve is cashiers who ask “Do you want your receipt?”
Of course I do.
When a customer leaves behind a receipt for $21.95, the cashier can void it, put it back in the drawer, & pocket the $21.95 cash.
The drawer then totals up exactly.
Ah ha.. Maybe that is why some cashiers look annoyed when you say you want your receipt.