Sure, caring that much about a penny is silly, but here are the two players here: 1. Cashier whose register will be counted at the end of the night, and any discrepancy is gonna get noticed. ("You only get a talking to at X dollars" isn't the same as "They literally don't take note of your till being off if it's under X dollars," to think otherwise is stupid.)
2. A woman who literally HAS enough money to pay for it in cash, but doesn't want to break an extra dollar, and is so angered by this offense that they claim they're gonna complain about it.
The only reason to think the cashier is in the wrong is if you're the woman who got butthurt over a penny. Anyone else arguing it is bait.
like i said, if she was misbehaving, then you dont wanna help her and that is understandable.
but those that are nice, why not take one out from your pocket and grant more reputation from people and love for your store.