I don't think this analogy is a very good one. Grain that has gone bad has close to zero utility. But office space in a city has tons of utility. It could be c

I don't think this analogy is a very good one. Grain that has gone bad has close to zero utility. But office space in a city has tons of utility. It could be converted to residential space, for example. A better analogy might be a sudden shift in tastes that caused the demand for grain to drop. The grain could still supply markets for animal feed. And the farms that planted grain this season can be converted to some other crop.