Trivia: The precis for Croc Dundee is a New Yorker travels to Australia, finds an Australian man, takes him back to New York, falls in love with him, drops her current beau and marries him. This mirrors reality. Linda Kozlowski married Paul Hogan after meeting on this film. He left his wife for her. In the sequel the characters return to Australia for protection, loved it and stayed. Likewise the real life stars moved back to Australia and lived in Byron Bay for 17 years or so.
Trivia: It's evident Foster's Lager was a sponsor, as many signs for their brew are visible throughout the movie. Paul Hogan even endorsed this brand and appeared in advertisements and TV commercials. While Fosters was and is available in Australia, it's relatively rare and not very popular, it's much more so in the US and UK.
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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