It’s true! Some long time ago for more than a year I lived on the beach at Mombassa so have some first hand observations. European females would come on holiday to the beach hotels specifically to have sex with a local African. There was even a phrase for it, modesty prevents me from using the actual words but in essence they come for the “African Experience”. Things have changed since then and now the local lads have caught on and are making a business out of it, but in those days there were very few handsome dark guys around the bars and the women went for just about anybody, waiter, gardener, garbage man they just did not care as long as he was black.
The worst or perhaps the most determined were the Scandinavians and surprisingly the Germans (Hitler would spin in his grave, if he had one) Seemed the fairer the lady the blacker she wanted the guy. I am not talking about fat old bags but gorgeous slim blond blue eyed darlings. The western guys and us few “permanent” tourists would not get a look in with these gorgeous girls. This was in the days when most things could be cured with a jab of penicillin and before AIDS became a major issue. I wonder what contribution those women made to the AIDS statistics back home in the following years?. As I said this was a long time ago and things have got more “sophisticated” but it happened and in those days it was all very basic.
For the last few years I have been living on a beach in Thailand and again have some first hand observations. Yes there are some Western women with Asian girlfriends but not so many, far more Western lesbian couples holidaying together. Quite a few Western gay couples but most of the men come alone finding a partner here. Some Western women really go for the local lads and want nothing to do with Western guys while Western men go for local boys or ladyboys and of course the girls.
I don’t know about underage sex and girls being forced into prostitution (all the ones I know love it) except what I get on the news. Anything is possible in Thailand but I must say the police do try to keep things under control by 1am closing, raiding clubs and checking for underage kids. Every one has an ID card but there are ways round that! 
Are Australians “Westerners”??? 