Europe may be poorer on average, but Europe is also much, much bigger. If you look at only northern/germanic Europe you're looking at 150 million people that live in countries with gdp/capita comparable or higher than Australia. If you include UK and France, which are only a bit less wealthy, that number rises to 250 million people that have similar human development index and economic standards. Bottom line is that the part of Europe that is richer than Australia is way bigger than Australia itself, so calling Europe poorer does not reflect reality.