Overseas grocery markets are more competitive than Australia's duopoly-dominated sector, according to the under-scrutiny industry's third-biggest player.
Representatives of German discounter Aldi on Tuesday faced a second day of public hearings at an Australian Competition and Consumer Commission inquiry scrutinising supermarkets.
Unlike dominant players Coles and Woolworths, which control about two-thirds of grocery sales across the nation but are focused on Australia, Aldi operates around the world.
Counsel assisting the inquiry Naomi Sharp SC said that meant Aldi executives were uniquely positioned to understand the competitiveness of the Australian market and how it compared globally.
Aldi national buying managing director Jordan Lack said more competitors in overseas markets meant they were less likely to be dominated by just one or two major players.
"I would observe that there is increased competition in those markets," he said.
"As compared to the Australian market?" ACCC deputy chair Mick Keogh asked.
"Correct," Mr Lack said.
But questions about whether Aldi operated with higher margins in Australia than overseas were objected to based on commercial sensitivity.
Instead, they will be answered in a private hearing, although some details could still make it into the commission's final report.
The consumer watchdog noted in an interim report it took two decades for Aldi to establish its fractional market share in Australia, suggesting issues with competition.
The inquiry was earlier told the chain attracts about 10.5 per cent of the market and is looking to bring extra customers to its almost 600 stores, rather than open in more sites.
Officials for Coles, Woolworths and Metcash - the parent company of IGA - will front the commission's inquiry later in November.
Assistant Competition Minister Andrew Leigh said more competition in the supermarket sector could get profits down to "a more normal level" but the inquiry was not just about prices.
"This is also about how you treat suppliers," he told Canberra radio 2CC.
"It's about the unfairness in the contracts, it's about concerns of capricious behaviour by the buyers for the major supermarkets and how that affects the smaller supermarkets."
However, Coles chair James Graham told shareholders supermarkets had been "targeted" as a scapegoat for broader cost-of-living issues.
"There has been a wider ambition of some behind those inquiries to seek to perhaps provide answers to more difficult issues which have been arising from ... inflation," he said.
The federal government will provide a $30 million funding boost for the commission to continue patrolling the supermarket sector.
It has also proposed changes to merger laws and a mandatory food and grocery code of conduct, carrying multimillion-dollar penalties for serious breaches.
The ACCC's final report is due in February.
