China has a growing middle class, and a growing class of perpetually single men. They need to stop the middle class from becoming so affluent so quickly (where do you park 400 million cars?), and they need to find jobs for the millions of sad horny guys who could easily become revolutionaries. If the cost of food rises a few percent here and there it bleeds excess capital out of the system, inconveniences a few on the long tail, but as a whole (remember, China thinks long-term, and like a single organism) the economy will be better off.