Speaking as a farmer, these are the prices required to remain profitable. I'm sure it wasn't covered here, but prior to 2008 we were seeing numerous farmer protests against the destabilization of our food sector. And then, all of a sudden, the prices rose. Maybe it was purely coincidence with investor actions, but I have always felt it was something else.

Though it raises some interesting ethical questions. Is it better to have the farmer subsidize the poor by not turning a profit, or is it better to have the farmer turn a profit (the goal of the business) at the cost of starvation of others?

At some point the farmers have to turn a profit. Maybe not every year, but most years. Otherwise some percentage of farmers will get out of the business and do something else. The price will rise until it becomes profitable.

Over the last few decades the real problem has been food is too cheap. First world governments are subsidizing food production to the point that a farmer trying to grow rice in southeast Asia can't compete with imported rice shipped from California. So that farmer moves to the city and gets a job making Nikes.

When there's some disruption in food production thousands of miles away all of the sudden people are starving because everybody is making shoes instead of growing food.

Good point, and of course there are the government farm subsidies too, which could go to the poor instead if the farmers were profitable, certainly here in Europe the subsidies have not necessarily achieved the right goals, as there is still extensive poverty in agriculture. There are also buy side issues, such as concentration of buyers. And in the UK I see farm land prices are rising fast, which will reduce much of the potential profitability long term.