Many farmers are subsidised specifically so that food is over-produced in most years, specifically to ensure than in bad years people don't go hungry.
Corporations may indeed be taking advantage of this, demanding prices so low that the farmers don't get the benefit of those subsidies. However:
> buy the stuff and sell it at a premium later
Is the point of a futures market. Futures let people trade a thing before they even know how supply and demand will balance, guaranteeing a price for the producer and letting them plan purchases of machinery and maintenance, with the risks (in bad years) and profit margins (in good years) going up the supply chain.
Another reason why most countries subsidise their agriculture is because in times of war you don't want your enemy to starve you. That's mostly about high calories foods, not fancy salads though.
It would be just easier to not wage war by the way.
Can't think of many countries besides Canada and US that would not starve in NATO if such a necessity arose, and that's because they produce lots of cereals.
All the other countries in NATO are major food importers.
>All the other countries in NATO are major food importers.
All apart from France, Netherlands, Spain, Denmark, Poland, Hungary, Lithuania, Turkey, Italy and Ireland.
Interestingly the US is borderline now depending on how you measure food imports and exports.
Being a major importers of olive oil is probably not such a big deal. The EU is pretty self-sufficient for food, for example - can change a bit the food and agg mix if needed (and some countries have emergency stores as well).