The retail workers' union has reiterated calls for the South Australian parliament to legislate Easter Sunday as a public holiday, to stop workers missing out on entitlements.
While Good Friday, Easter Saturday and Easter Monday are public holidays in South Australia, Easter Sunday is not.
Easter Sunday is a public holiday in every other Australian jurisdiction except South Australia and Tasmania.
The South Australian branch of the Shop, Distributive and Allied Employees Association (SDA), the union representing retail, fast-food and warehousing workers, said staff working on Easter Sunday were missing out on public holiday entitlements.
The union called for the government to ensure the regulations change before next Easter.
"It's incredibly disappointing that today South Australia is the only place on the mainland where Easter Sunday is not a public holiday," SDA SA secretary Josh Peak said.
"And that means South Australian essential workers who are keeping our state going today are going to work without public holiday penalty rates."
Mr Peak said most of the state's retail stores were closed today, with the exception of the CBD.
"What that actually leads to is many workers being required to have the day off, because the store is closed ... so they're having the day off, but not being paid for it," he said.
"Whereas everywhere else, or if it's a normal public holiday, if you have the day off, you're paid your normal wage.
"And that's the way it should be on Easter Sunday as well."
Parimal Gotecha, the co-owner of a burger shop in the CBD, said he believed workers should receive penalty rates for working on Easter Sunday but he can also see the cost impact for small businesses like his.
"The market is really tough for the hospitality industry due to the inflation rate and all that stuff," he said.
He said trading had been "really quiet" so far on Easter Sunday, but he hoped it would pick up tonight.
"We'll see how it goes," he said.
He said he will still open his burger store next year if Easter Sunday becomes a public holiday.
"It's a win-win situation for everybody," he said.
"It's a win-win for worker and business owner as well."
On Sunday, SA Deputy Premier Susan Close acknowledged Easter Sunday was a "strange" day compared to other public holidays, and said public consultation was underway on the issue.
"We recognise that South Australia is largely out of step with the rest of Australia for Easter Sunday, where elsewhere it's declared a public holiday," she said.
She said Easter Sunday was an "odd day" due to the state's regulation allowing certain shops in the CBD to trade today, unlike other metropolitan shops.
"And the reason we are more strict about shopping hours is because we want to protect the diverse range of retailers that we have," she said.
Mr Peak said it would be "astounding" if the government did not take action to make Easter Sunday a public holiday following the review of the Holidays Act.
"It should have been fixed by now, but the public holiday review gives us a real opportunity to fix it," he said.
"Ultimately it's the parliament that needs to pass the law here ... so that workers and businesses get certainty going forward.""