The alleged cash rip-off was described as opportunistic by Australian Competition and Consumer Commission boss Rod Sims who said companies “misleading” consumers face penalties of up to $1.1 million .

Among the 170 complaints to the ACCC, is a bakery who told customers that bread prices would increase from $3.70 to $3.80 from May 25 – and a gym which encouraged a customer to sign up to a long-term membership on the premise that they would “get a discount on the carbon tax”.

Mr Sims said this is just one of 170 complaints they have received for misleading or deceptive behaviour, price gouging or potential scams in relation to the carbon tax.

“This is a classic example of an opportunity businesses will see to take advantage of consumers, to dupe them into paying too much or paying for a product they don’t need,” Mr Sims told The Sunday Telegraph.

“Yes, some businesses are going to face higher costs, and it’s totally appropriate that they pass those costs on, but what we are trying to stop is people taking advantage of the situation to justify a higher price than is appropriate.

“If you think about a wedding reception, you’re going to have the alcohol, food, and then the establishment itself obviously providing electricity, but you can’t imagine that’s – for the time they’re in the wedding hall – $5 per head.

“It’s certainly something that we’re going to look into, and it’s also been said to us by the complainant that other people have been affected as well. The worry we have is they’re using the carbon price as a hook to basically sell extra time on the gym membership,” Mr Sims said.

“When the person bought their original membership they were told it was a fixed price, and then the trader got in touch with them and said the price was going to go up due to the carbon tax.

“They then advised though that if the complainant was willing to sign on for another 12 months, there wouldn’t be an increase in price . . . and if they signed on for another 24 months then the membership fee would actually decrease.”

In most cases the ACCC will issue a warning, but the watchdog can also exercise new powers requiring businesses to substantiate their claims. If a business fails to do this, public companies face penalties of up to $1.1 million per breach and private companies face fines of up to $220,000.