Supermarkets have quietly axed up to a fifth of economy range items - despite claiming to help cash-strapped families.
The products in question include bread, baby products, fruit, vegetables and ready meals.
The shopping website MySupermarket.co.uk has revealed that Tesco has stopped 21% of its Everday Value range, while Sainsbury's has cut its Basic range by 15% and Asda Smart Price is down by 7%.
This comes as Tesco launches a new Brand Guarantee scheme to see customers refunded with cash straight from the till if their basket of goods is cheaper elsewhere.
Ulster University retail expert Donald McFetridge said consumers were getting a raw deal.
"Shoppers are the casualties of supermarkets desperate to claw back profits," he said.
According to MySupermarket.co.uk, Tesco slashed the number of products in its Everyday Value range from 683 to 541 - down 21% in the past year.
Sainsbury's reduced its Basic range by 71 (from 483 to 412) - or 15% - during the same period, while Asda's Smart Price offering went from 349 to 323, or 7%.
A Tesco spokesperson said: "As part of our work to make the shopping trip easier for customers, we have been simplifying our range."
Sainsbury's and Asda both said they regularly reviewed products based on customer demand.
Tesco, which has more than 50 stores here, has introduced a new scheme whereby shoppers will receive an instant refund for goods that can be bought cheaper at other supermarkets.
It heralds a major shift in strategy. Previous schemes gave consumers a voucher.
The supermarket said its overhaul comes after almost half of shoppers said they forgot to use their vouchers and 16% said they even lost them before they could get their money back.
Post-recession, price-matching schemes have been the major battleground for the big grocers.
But as a result of food deflation and the aggressive growth of cheaper rivals such as Lidl, profits have been eroded because supermarkets have been forced to sell more goods for less.
They are already going toe-to-toe on branded products and staple own-brand goods, but the latter has been pared down over the past year, as MySupermarket.co.uk has shown.
Mr McFetridge said the supermarkets were sending out a mixed message. He added: "On the one hand they have been quietly scaling back on their economy range, while also actively promoting their price-matching schemes."