There is general agreement that a world food crisis is occurring. Biofuel (especially ethanol made from corn) has borne a large part of the blame. I'm not convinced that it overshadows other factors — speculation, water scarcity and the effect of the price of oil — but it certainly allows for the most vivid imagery.
Once again I am reminded of a passage from Dune. The titular planet is mostly desert, dry to the point where water is currency and windtraps are constructed to harvest airborne moisture. Two characters talk about trees planted brazenly outside the mansion of the ruling Duke:
The way the passing people looked at the palm trees! She saw envy, some hate…even a sense of hope. Each person raked those trees with a fixity of expression. … "Those minds," he said. "They look at those trees and they think: 'There are one hundred of us.' That's what they think." She turned a puzzled frown on him. "Why?" "Those are date palms," he said. "One date palm requires forty litres of water a day. A man requires but eight litres. A palm, then, equals five men. There are twenty palms out there—one hundred men."
And in a CBC article today, a statistic from the Sierra Club which I hadn't previously heard:
…it takes five hectares of cornfields to produce enough ethanol to run a car for a year. The same land could feed seven people for a year.
Reality being naturally less dramatic, the hungry people are on other continents, and we are spared being "raked with a fixity of expression" as we climb in our sedans and SUVs for the morning commute. If we experienced those glares directly, I don't doubt our behaviour would change much faster.