why are these child workers growing export crops destined for first world consumption instead of growing their own food? It must be because they're stupid and never read Economics 101
spoiler
It's because the IMF and world bank force them to privatize and deregulate their economies, and take out high interest loans denominated in USD, and to grow export crops instead of growing their own food, and to import their food from first world countries, leading them to become imports-dependent and very easy to control with threats of sanctioning. Also their debts are in a currency that they do not use (USD), meaning they have to earn that currency through the already rigged trading scheme in order to pay back their debts to the people doing the rigging.