I think you'll find escorting/camming is the
EASIEST option, rather than the
only one for them.
But having said that, the curcumstances in 'developing countries' (or worse) are far different than in the West etc... and I don't only mean socioeconomically. In Asian countries in particular, the family bond is a lot closer than in the West. Oftentimes the families themselves endorse their children to 'escort' for want of a more respectable way to survive and there is no 'shame' in what they do, for it's to support their family (not to support drug habits and the like, vices that are synonymous with Western vocations of this kind).
A pertinent example in the OP's *
looks at flag* case might be the Philippines - Pinoys faught side-by-side with the Yanks against the Japanese in WWII and the only thing they got in return was the dubious privilege of becoming said Superpower's personal island brothel and favored sex tourist destination!
The US also influenced Filipinos in the attitudes towards materialism and money - it's very evident when comparing them to, say, Thais, who are less about $_$ and more about companionship and acceptance (hence the putative jealously Pinoy LBs harbor of Thais, which I'm starting to learn is not merely for the latter's purported 'superior beauty'). Then of course there's the
religion factor, which needs little exposition other than to say Buddhism is about forsaking desire and while Catholicism/Christianity is well...
http://www.youtube.com/watch?v=K9JjgRi7BFw 
So I wouldn't be too hasty to condemn based on what are likely relatively limited on-line experiences. There are always bad apples and there are often mitigating circumstances.