Even if such a "sharp rise and fall" were not just fear mongering
What? Starvation is a historical fact, and in fact still continues today. It is not fear mongering, it is what happens when you do not have enough food.
That kind of reasoning applied about 300 years ago.
I'm not talking about famine, a la Irish potato or Ethiopia. I'm talking about broad starvation. Dust bowl, Great Depression, that sort of thing. You don't need famine to destabilize the country.
But sharp rises and falls in food prices are almost always the result of misguided government policies.
Drought? Flood? Pests? Disease?
Between markets, insurance, worldwide production, and modern food storage, these concerns simply do not exist.
They still exist, but the interplay is much more complicated and harder to predict. What would a fuel crisis do to overseas shipping? What about a war? You mention food storage... just who is storing excess food without some subsidy to do so? Where is this excess food shipping capacity that you will tap when domestic production hits a snag?
I am going to store the food, trade options, and/or diversify geographically.
And what happens when prices are high? You sell out your stocks and there is nothing left in inventory should something go wrong.
All of that stabilizes and regulates food production better than any government policy can.
I'm not suggesting central planning or anything of the sort. I'm suggesting subsidizing food production. You are absolutely right - it will ruin the efficiency of the markets. However, I contend that paying a little extra is worth the insurance.
Let's say that you're argument has won the day and that a pure market approach will keep us all fed and happy. Is it not fair for me to point out that it is impossible to achieve a pure market approach? That corruption and crime will always exist? Couldn't corruption or fraud undermine the market system when a stressful event occurs? Why shouldn't we accept that as fact and build in some safeguards, even if it spoils the efficiency a bit?