Retail food prices have climbed more than 4 percent in the last year, and a similar hike is projected for next year. Riots have broken out in developing countries over food shortages. Schools are being forced to change their lunch menus. Some consumers, reacting to a rise in the price of rice, have made a run on stores – prompting Costco, Sam's Club and other retailers to limit how many bags they sell to individuals. Consumers are hurting, yes, but growers of corn, wheat, rice, cotton and other crops are loving life these days. Corn has hit a record $6...