An Australian supermarket chain has made a potentially dangerous move that could drastically change how we buy groceries as more of us feel financial stress from the growing cost of a weekly shopping basket.

Independent chain Drakes, which operates in South Australia and Queensland, is the first supermarket Down Under to offer customers a buy now, pay later (BNPL) option after introducing Afterpay across its 65 stores.

The service allows shoppers to pay for items in four interest-free instalments every fortnight and imposes late fees if payments are missed. The move has come under fire from welfare groups and consumer experts, who warn it could create a debt trap for vulnerable consumers in the long run.

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Drakes Supermarkets director John-Paul Drake admitted the company held similar reservations about the payment method, but decided to introduce it to meet customer demand.

"[At first] I looked at Afterpay like, 'Well if you're using Afterpay, that means you're struggling to pay for something,' and when we started to actually look into it, that wasn't the case at all," he said on ABC Radio.

Drake said the service is a "good fit" for the retailer's young customers, and after looking into buy now, pay later providers, Afterpay was "quick to come to the party".

Financial breathing space or slippery slope to crippling debt?

A recent Finder survey found 42 per cent of Australians said their grocery shop was causing them financial stress, more than doubling the figure from three years earlier.

The average household spent $185 on their weekly grocery shop in September, a $15 jump from the previous year that works out to be $780 a year.

With costs like energy bills and petrol continuing to rise, relying on a BNPL service for a weekly expense like groceries could spark a dangerous debt issue.

"Spreading payments with Afterpay can mean financial breathing space when buying big-ticket items, but relying on it as a financial lifeline to pay for basics like your weekly supermarket shop can be a slippery slope to getting into debt if you're already struggling and can't keep on top of repayments," Consumer and personal finance expert Sue Hayward told Yahoo Finance Australia.

A 2020 report from corporate watchdog ASIC found that some consumers were "suffering harm" as a result of buy now, pay later schemes, with 19 per cent of users unable to purchase essentials.