A move to remove New World and Pak'nSave online shoppers' ability to sort items by price is "surprising and disappointing", Consumer NZ.
The change had been made "quietly" to both supermarket brands' websites, the consumer advocacy group said.
Consumer NZ spokesperson Chris Schulz said shoppers were used to having the option, and other retailers, including The Warehouse and Woolworths, still offered it.
But he said New World and Pak'nSave now defaulted to sorting by popularity.
"Such a move may limit options for shoppers and ultimately bolster supermarket profit margins at the expense of local suppliers," Schulz said.
Consumer NZ said Foodstuffs told it that it was upgrading its digital platform to improve the online shopping offering, including more transparent unit pricing. A new sorting feature would be added soon, it was told.
Schulz said it was bizarre. "This change could hinder consumers from making informed decisions about their purchases."
Photo: RNZ
Without the lowest price option available, home brands dominated the search results, he said.
Marketing expert Bodo Lang, from Massey University, said he had been so surprised to hear of the change that he checked it himself.
"It is another move that will make grocery shopping more difficult and less transparent for New Zealand shoppers.
"While not every shopper would have used the 'price sort' function, many shoppers would have. New Zealand's most vulnerable shoppers are likely to be disadvantaged the most by the surprise removal of this function. This restriction is likely to cause further financial hardship for New Zealand's most vulnerable households."
He said it seemed counter to the spirit of changes like offering unit pricing.
"Acting in the spirit of making unit prices available would have meant that supermarkets should have added 'unit pricing' as a sorting function to their websites. In this context, removing even a basic 'price sort' is extremely disappointing.
"My experience with e-commerce platforms is that even the most basic platforms can sort products by price. This suggests that Foodstuffs may have deliberately disabled this functionality."
He said while the websites allowed shoppers to only display products on "sale", research had shown supermarket specials were often not all that "special".
"In other words, this function is unlikely to show consumers the least expensive products."
Research showed consumers reacted "highly negatively" if their choices were restricted, he said.
In a statement, Foodstuffs said it was upgrading its digital platform and "improving our e-commerce offering with more transparent unit pricing".
It would "soon" add a feature allowing customers to sort product by price, a spokesperson said.
"We're aiming to have our new price sorting tool live within our Pak'nSave and New World websites by mid-November. Meanwhile, customers using our Pak'nSave and New World apps continue to have the option to sort their search results by price.
"Our goal is to make finding products online quick and convenient, whether customers are searching or browsing categories."
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