Costa Rica (stick with me here) is world-renowned for it's coffee, which makes up 15% of the GDP of the entire country. And years ago, when I visited a coffee plantation in Costa Rica, they told me how they make decaffeinated coffee - and that, while decaffeinated coffee was a product in demand in Costa Rica, there wasn't a single de-cacfeinating plant in the entire country. It was cheaper for them to ship the coffee to Germany to be decaffeinated, then shipped back to Costa Rica for more processing before being sold. Why is this relevant?

not to mention whatever processing then export of secondary products eventually goes to developing countries.

Because it's entirely possible that they're processing the base grain into more refined products before it heads to it's final destination.