https://www.choice.com.au/supermarketsurvey
It seems that Coles' "down down" and Woolworths' "cheap cheap" everyday low pricing strategies are no match for Aldi's lower cost bases for labour, rent and other general and administrative costs, as Aldi retains its crown as cheapest supermarket.
Our basket of leading brand products cost $87.29 more at Coles ($174.97 excluding specials) and $89.09 more at Woolworths ($176.77) than a basket of equivalent products from Aldi ($87.68). So by foregoing leading brands you can save about 50% off your grocery bill by shopping at Aldi.
The difference between Coles and Woolworths was less distinct – just $1.80 between them excluding specials for the leading brand basket – reflecting the intensive process of price monitoring that exists between the duopoly.
Independent chain IGA returned the most expensive basket – 8% more expensive than the same basket of leading brand products at Coles (excluding specials).
So if the opinion holds that the Aldi brands aren't as good, the leading brands are making inferior products for Aldi, or any other private brand?