When food prices were more reflective of production costs many of the poor certainly did make better use of perishables. They would be using the organs and cuts of meat the rich didn't want, purely out of necessity (assuming they were lucky enough to be able to afford meat, many weren't). It was that or go hungry and often they still did go hungry. I don't know if it ever stopped the rich from being wasteful, though.

I think it's hard to balance between over and under supply. Under supply would certainly mean people would think a bit more about their food and usage, but do we run the risk of even more going hungry? Heck, today with the over supply we have, people still go hungry even in first world countries.

I certainly think we're going too far when it comes to cheap food, though. Supply is going to completely collapse if these farms and companies go under because we don't want to pay what it costs to produce.