Yes the yanks more moralistic than the Aussies. Everything stated by Dave is right. Lots of stings w cops buying then arresting the lady. Oz we got legal brothels (in most states) and legal sex work. As aussie comedian Jim Jeffries says about Americans going on about being "the land of the free": "in Holland, you can smoke weed whilst fucking a hooker in front of a cop. How dare Holland not be called the land of the free! Do you honestly think you are competing with holland?" lol.
Too many wowzer religious types in USA. But interwoven is racism too. These same religious types who pushed for prohibition were partly motivated by all these unwashed immigrants coming into the USA after WWI and these immigrants liked to drink.
But the USA is just more extreme in every direction. Thus there are entirely free love types and Taliban style Christians. And the loud win the day in the usa, not so much the smart.