Realistically if the big chain stores were serious about this, they would create Australian Only shopping aisles. Probably only need 1 aisle in Woolworths or Coles.
It is not up to them, it is up to us to buy Australian. Everything is labelled. Sometimes it is hard to find where a product is made, but in 99.9% of the cases this is to hide it, it will be there somewhere. If it is made in Australia it is shouted out on the packaging pretty loudly. I refuse to buy any food out of China. The fact their own citizens covertly hoard and ship back Aussie baby formula and similar products speaks volumes to me.
When I talked to Dawn about which vices were made here, I told them that I wanted to buy Australian, both for the quality and for the fact the $ and jobs stay here. The representative I spoke to actually thanked me for thinking this way and for supporting Australian manufacturing. They told me that they keep an Aussie range and an imported range. There is nothing really wrong with the imported ones, they are quality gear, but they are made overseas and have a lower cost base but aren't as good as the local ones. They are certainly better quality than the cheap garbage you'd buy from a discount tool, hardware or auto store, but nowhere near as good as the local product.
I'm not against buying imported stuff if it is good quality and there is no Aussie alternative, and generally not of Chinese manufacture although some stuff made there is good. I always bought GMH/Holden but stopped doing that at VZ as they had no alternative for me to buy after VZ. My VZ Cross8 was my last Holden, anything after that sold by Holden was useless to me. Currently our two drive cars are Japanese (Lexus RX350) or Japanese where it matters (2011 SR5 Hilux driveline is all Japanese). My next car will probably be North American with possible local content (Ram1500 or maybe a Jeep Gladiator if a bolt on Supercharger kit is available). I'm even careful when I buy tyres, I want to look at them to see where they are made. I will not buy Chinese tyres. Sure they come from Korea, USA, Japan, Thailand, India etc, but they are not trying to conquer the world just trying to exist in a global economy. The Toyos on my Hilux are made in Japan.
When you eventually get an Aldi in Cairns look past the pain in the @rse checkouts and quirks, and look at where most of the food and cleaning they sell comes from. It is primarily Australian. I don't buy much food there, but I do grab a few things that I recognise when we do a cleaning products shop. The cleaning products are so cheap it is ridiculous.