Although there are Australian dollars, the main currency in circulation is Hong Kong dollars, and the prices of all commodities are basically Hong Kong dollars. The exchange rates of Australian dollar and Hong Kong dollar are the same. Renminbi is also very useful in Macao.

You should be able to ask for RMB when you swipe your card. If you want to swipe Hong Kong dollars, others will convert the amount to be swiped before swiping your card.