In almost a decade of shopping there this has never happened to me and I'm one of those bastards that reads the receipt as I'm boxing the groceries before I lea

In almost a decade of shopping there this has never happened to me and I'm one of those bastards that reads the receipt as I'm boxing the groceries before I leave. I joked with a cashier about this, once ... she said, deadpan, "it beeps when it scans". I'm guessing they're listening for two beeps when they're expecting one? The store keeps stats on the cashier's times so I'd imagine there's some training and probably some things only an Aldi cashier could speak to about how they manage to be quick, accurate and deal with the 30 or so customers a day who (used to) come in expecting to pay with a credit card (they're now accepted at Aldi in the US).