[WS:] So if they actually paid the promised $5k, would everything be ok?
I think what economically-minded people miss in it is that not everything is about the right price. There are some deeply ingrained norms in virtually every culture that proscribe turning humans into commodity - hence the nearly universal rejection of slavery or cannibalism. This is of course not to say that slavery or cannibalism do not occur but that if they do they are legitimated by some very extraordinary artifice - e.g. burial ritual or dehumanization. Mere hardship is not enough (cf. the Donner party.)
Selling one's body or its parts belongs to the same category. People do it for various reasons but it offends those deeply ingrained norms.
Hence the need for extraordinary artifice justifying this practice. Claiming that it is "just wage work" or "everything is about the right price" is one of them. However those who use such rationalizations are fooling themselves, and if they really believe what they say, they are likely to suffer from Antisocial Personality Disorder http://en.wikipedia.org/wiki/Antisocial_personality_disorder (which is a prerequisite to become an economist :))
Wojtek