The Down Down sticker was then plonked on the front of the lozenges at the “discount” price of $6 on November 9.

Woolworths is alleged to have done something similar on Oreo family packs between November 28 and December 20, taking the price from $3.50 to $5 before selling them at a “discounted” $4.50.

All of this occurred in the December quarter of 2022 when inflation reached a peak of 7.8 per cent. Food inflation lifted by 0.9 per cent that quarter, taking the annual rate to 9.2 per cent. Prices for some goods, such as biscuits, were climbing at more than 10 per cent.

Just a few weeks later, the RBA lifted the official cash rate to 3.35 per cent.

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High-priced Strepsils and Oreos were not the only reasons for the RBA’s decision.

But if the ACCC’s argument is proved, it does undermine all the experts and economists who claimed there was no sign of price gouging causing inflation. The evidence, as mapped out by the competition watchdog, is sitting there in your kitchen cupboard.

Politically, the fact two such high-profile companies have been implicated hurts the business sector.

Last week, the Business Council of Australia ripped into the government for everything from red tape to industrial relations reforms with claims not enough was being done by Canberra or the states to reduce inflation.

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Both Coles and Woolworths, which Cass-Gottlieb noted sell millions of products to millions of people, are council members.

It’s not going to get any easier for the sector. On the same day that the lawsuit landed, the government released its mandatory supermarket code of conduct for discussion while CHOICE is due to produce its latest quarterly report on supermarket prices later this week.

By taking this action, the ACCC is showing that – unlike other regulators – it is prepared to go hard with big cases. Any other business that thinks it can use general inflation to push up margins by lifting its prices will probably think twice after today.

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