Evil evil Wal-Mart. Crushes the competition, strong-arms its suppliers and perpetuates a consumerist monoculture. What does Wal-Mart have to do with social change - at least, 'positive' social change?
Well, it turns out that Wal-Mart has just announced a five-year plan "to cut prices on healthy food and press its suppliers to cut back on sodium, sugar and trans fats in their packaged products."
My guess is that this change - if they stick to it - will do more to counter the rise of obesity than any government program.