Shoppers cheated by supermarket scanners

Barcode scanners in supermarkets are regularly charging shoppers wrong amounts because incorrect prices have been programmed into the system, a new study has found.

Common errors include failing to load in sale prices, meaning shoppers buy products believing they are getting a bargain but end up being charged full price.

AUT business academic Dr Paul Pickering said he had expected the study to confirm a scanner error rate of at least 4 per cent - meaning one in every 25 items scanned was incorrectly priced, usually to the shopper's disadvantage.

But the result of the preliminary study has led Pickering to widen his research to study till receipts from 2000 customers to find out how much they are being overcharged.

The plan to widen the research project has won support from Fair Go consumer advocate Kevin Milne. "For all of us, it's worth remembering to keep an eye on your receipt. It's worth knowing that these machines aren't infallible."

Pickering said fewer than half of shoppers checked their bills and had no idea of the errors that were made.

"I think it should be of real concern to consumers. If you translate it into monetary terms, it has to be in the millions of dollars.

"The implications from a study like this are massive. Consumers in New Zealand are not making enough noise about it yet," he said.

In one case, a supermarket offered bottles of coke for 99c, but displayed the wrong size bottles under the sign, and charged the shopper $3.

In another, a cooked chicken was advertised on sale for $6.99, but the original price of $11.99 was charged at the checkout.

In this case, Pickering said, the mistake was spotted and the customer was given the chicken for free.

But more often, retailers respond badly when errors are pointed out.

Shoppers who took part in the study reported sales people "rolling their eyes" when asked for a refund, having to fill out forms to get a $2 overcharge returned, and being offered cash refunds only when the original purchase was by credit card.

"The errors are happening right across the retail area, particularly large-scale stores," Pickering said. "When you're pumping 100 items through a till, it's much easier to make a mistake and much more difficult for the customer to keep up with the things flying through the scanner."

In the United States, scanner price mistakes have resulted in court cases against big retailers.

In October, Target Corporation was fined US$1.7 million ($3.4 million) for displaying out-of-date price stickers which showed a lower price than the amount charged at the checkout. Overseas studies have found that the introduction of barcode scanners cut the error rate from 11 per cent to about 4 per cent.

Pickering said his survey of 25 shoppers showed the problem was at least that level in New Zealand, perhaps higher.

Pickering said he'd like to see companies here make efforts to solve the problem. "There's an opportunity for these big businesses to say, 'The problem exists, we haven't been able to sort it out completely, but we going to do something about it'."

Foodstuffs Auckland retail general manager Murray Jordan said the cooperative, which includes the New World, Pakn'Save and Four Square chains, had a robust price-checking system including manual checks as well as automatic updates.

When errors were discovered, he said, the customer was refunded and the national office was contacted to ensure the mistake wasn't repeated elsewhere. Jordan said figures on error rate weren't available.

Retailers also follow a scanning practice code administered by GS1 New Zealand, the society that issues product barcodes.

The code says where there's a difference between the sticker price and scanned price, the shopper should be charged the lowest.

GS1 chief executive Peter Stevens said fewer than 20 complaints a year were received. The grocery industry was among the best at making sure prices are right, he said.

"The price that's on the shelf is the price that's on the till, because the systems are incredibly good. The problem areas are around promotional items."

A study by GS1 this year showed the use of barcode scanners reduced costs for retailers by $1 billion a year.

- ADDITIONAL REPORTING: Lia Nicholls