Australia has the best supermarkets in the world, hands down. Why? Because we grow and produce almost all of our fresh produce, dairy, meat, and seafood. There are some exceptions for seasonal things, but the Australian climate allows for almost everything we eat to be grown here. The solution to this problem in the US and the UK is less globalism, not more.
I'd rank Australia near-bottom of the dozen or so countries I've lived in/visited when it comes to supermarket quality[0]. Homogenized, bland food pumped full of water, optimized for profitability, shelf-life and appearance rather than nutrition or flavour.
[0] to be fair, the USA is even worse.