Audio problem: In the scene where Mick returns from the corroboree and Sue asks if he is telepathic, in the US version of the film, he responds with "You're a woman and a reporter, that makes you the biggest busy body on earth". In the Australian version, instead of "busy body", it is "sticky beak" which means nosy in Australian speak. In the US version, you can see him mouth the words "sticky beak", but it is dubbed with "busy body" for American consumption.
Audio problem: When Mick first meets the two hookers outside the bar, their pimp walks up. He then makes the comment to Mick, "You gonna talk all night, or you gonna screw one of 'em?" Watch the pimp's mouth. He very obviously starts to say something other than "screw" as he mouths an "f" sound. But the camera clicks away to Mick's face and you hear the word "screw". Later in the movie the "f" word is used by the pimp. Must have been a post production edit to keep the PG-13 rating from becoming an R rating.
Answer: It is a party thrown by one of Sue's socialite friends, presumably the husky-voiced woman whose crotch Mick grabs. The party is not "full of hookers", Simone is there as the hired escort of the old man she is dancing with, who Mick naively believes to be her father. We can assume the old man paid for Simone to be his date to the party and likely for some time alone with her afterwards. There is no stated reason for why the party is being thrown.
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