Coles and Woolworths are being urged to scrap member-only prices for customers who have joined membership programs.
A parliamentary hearing into supermarket prices will take place in Melbourne on Wednesday, with consumer advocates to push for fairer prices at the check-out.
The inquiry was launched in response to allegations of major supermarkets price gouging customers, ripping off suppliers and strangling competitors.
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Choice will appear before the committee and urge major retailers to stop offering discounted goods to customers on loyalty programs.
The consumer group has also called for a ban on app-only discounts, as well as multi-buy discounts that aim to increase spending in store.
In its submission to the inquiry, Choice said the practices were misleading and deceptive.
“Member-only pricing is an unfair pricing practice, as it pushes consumers to sign up to rewards programs — providing their personal information and detailed purchasing behaviour in exchange for cheaper products,” its submission said.
“This is particularly inappropriate when applied to essential products like groceries, as everyone should be able to access affordable groceries without joining a membership program.”
Choice also took aim at “discounted” stickers on items whose prices have not been lowered.
“Consumers are drawn to the special sticker and are led to believe they are receiving a discount when, in fact, the price does not appear to have changed,” its submission said.
Primary producers will also appear at the hearing, including the National Farmers’ Federation, AUSVEG and Fruit Growers Victoria.
On Tuesday, the committee heard low prices for produce set by major retailers were making business unsustainable for farmers.
The price being offered by supermarkets to farmers for many products had remained similar to a decade ago, despite labour costs rising.
