If you ever thought your child was pocketing some of the money when running errands to the local dairy, think again - it's just as likely that he or she is being ripped off.
A Herald on Sunday investigation has revealed convenience store owners are routinely short-changing their youngest customers.
A concerned mother contacted the newspaper claiming that retailers were often giving her children incorrect change - so we set out to test the theory.
We sent three children along busy Dominion Rd in Auckland on a Wednesday evening. They visited 15 stores and, incredibly, they were short-changed in nearly half of them.
Nine and 10-year-old sisters Layne and Scout Blackwood and 11-year-old Paddy Devlin were given $10 notes and sent into shops to buy items ranging from fruit juice to a pack of toilet rolls.
They visited 15 dairies and superettes and were short-changed six times.
At a seventh shop, Dominion Superette, they were given just 90c change from $10 when they bought a litre of milk and a pack of butter. The owner would not give individual prices to explain the change but nearby superettes put the same two items at $8.50.
The biggest identifiable shortfall was 50c and the children lost more than 10 per cent of the total amount they spent.
Mother Jody Blackwood said she was shocked by the results. "I've been suspicious a few times in the past but it has been such small amounts, I didn't check it."
But she now realised the small amounts were adding up. "It could be $100 over a week. Both the girls are of the age where you expect them to be able to run in and buy something but they probably wouldn't check the change, they'd just assume it was right. It might be human error, but seven out of 15 times?"
Fresh World, at the Valley Rd shops, charged Scout $5.50 for a tray of eggs but only gave her $4 change from $10. When contacted, the manager, Lulu, was apologetic and said the staff member was new. She said Scout could return to receive the 50c she was owed.
Mobil Balmoral, where the sting team again lost 50c, was not convinced it had happened and said security camera footage would be reviewed. The manager wanted to see a receipt but the children were not offered one - the assistant threw it in the rubbish bin.
At Raams Dairy, the assistant told Paddy the amount he had to pay was $8.40 - but only gave him $1.40 change from $10. The owner, Chanchal Patel, was later apologetic and said the missing 20c was likely a mistake. "I'm sorry about that. Next time you come in, I'll give you the money back."
At Landscape Dairy, the owner, who would not give his name, rejected suggestions that the wrong change had been given - with some confused arithmetic.
Paddy bought a litre of milk, a loaf of bread and a bag of lollies and was told the total was $7.20. He was given $2.50 change from $10.
But the owner later said the milk was $2.80, the bread $4.70 and the lollies $1 - a total of $8.50. "I gave the right change," he said.
But the right change from $10 for $8.50 would be $1.50, not $2.50.
Consumer NZ said it hadn't received any complaints about children being short-changed. However, Consumer adviser Maggie Edwards said children were likely to be too embarrassed to make a fuss when they did not get the right amount.
Roger Bull, of the New Zealand Association of Convenience Stores, said his organisation covered only service stations and chain convenience stores, not dairies. But he was shocked by the results. "(Dairy owners) tend to be new New Zealanders who tend to be smarter than the average bear, or so they think. You can guarantee that they are good at the numbers."
He said if Mobil did not take action on the shortfall, his organisation would follow it up.
Retailers Association spokesman John Albertson said the results of the sting were disturbing. "The vast majority of transactions are done electronically so, whatever's on the card, there's a receipt to match it."
Associate Professor Carolyn Costley, at Waikato University, who has done research on ethics and consumer behaviour, said the results were appalling and deserved further investigation. "There's a lack of respect for customers, and children deserve respect too."
How much were the kids short-changed?
Fresh World - 50c
Mobil Balmoral - 50c
Landscape Dairy - 30c
Raams Dairy - 20c
Peters Island Food and Dairy - 50c
Eden Heights Superette - 20c