For goodness sake. Where is your friend going with her DH? There are hookers in the sort of places you find hookers (lots. I used to live in one such area) but they aren't universally present; 'leering' is in the eye of the beholder (there is certainly more looking), and labourers aren't being "shipped off" to labour camps any more than children are 'shipped off' home after a day at school; the 'camps' are where they live. And some are better than others. If your friend wants to engage her children with the issue, there are various expat 'support the labourers' projects she could involve them with.
And I have shown my arms in public places for the last 10 years and nobody has ever spat at me.
Portofino, I know what you mean about the child labour, but where child labour prevails, the child is generally the only/one of the only breadwinners - the job is there and the child's mother/father/uncle/aunt could have it if children weren't being used.
The mothers away from their kids I do find heartbreaking, especially the ones (usually waitresses) who will borrow your kids for a little cuddle - luckily my maid's son is all grown up; but at least these kids are getting an education, generally on the back of their mothers' sacrifices. I think it's pretty impressive that they are prepared to do that, and I don't know what the answer is (nor do I know the answer with regard to the bar girls - at least with the maids/waitresses/etc here, they are not selling themselves.)
As for the 'slave' labourers, as far as I have been able to ascertain it is virtually always the home country agencies who take money from the men. It isn't the case that every labourer here comes on that system; but it is an identified problem.