Market forces and food

In an old blog post on market fundamentalism I said:

I believe in using heavy taxation to push market incentives in the right directions. Americans are getting obese because, in part, sugar is cheap and readily available while fresh vegetables are harder to obtain. (Anyone who doubts the latter has been spending too much time in foodie places like my hometown; in much of America you can't find anything greener than iceberg lettuce for love or money.) We should tax sugar back into being a luxury, and subsidize the salad industry.

Recently I noticed Ezra Klein asking why is bad food cheap?

Put aside the externalities. The weight gain and the chronic diseases and the carbon pumped into the atmosphere. Bracket it, as my college political science professors used to say. There's a tendency to believe bad food is simply cheap. We make it like that because it saves us money. Sometimes, that's true. More often, it's not. Bad food is subsidized. Take high-fructose corn syrup. These days, the average American consumes almost 60 pounds of the stuff each year. Forty years ago, they consumed a pound or two of corn-based sweeteners. What happened?
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Sugar is pricey because the government, on the one hand, pays corn producers to sell high fructose corn syrup for below market cost, and because it won't allow the importation of cheap sugar from other countries.
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taxpayers are handing billions over to the meat and grain industries in order to convince livestock producers to sell their product at below market rates. We are funding this system.