A great vignette of international aid in Money as Weapon by Christopher de Bellaigue in the London Review of Books:-
Early in the occupation the coalition launched a drive to persuade people in Helmand province to plant wheat instead of poppy. One of the arguments that impressed the villagers was that they could get a higher price for wheat. But it so happened that around the same time USAID was giving out sacks of free flour, which had the effect of depressing the price of wheat. People went back to growing poppy.