This article discusses the problem:
The news on this front is not all dreary. Americans are taking steps to curtail waste. College campuses are taking away lunchroom trays that encourage students to take more food than they can eat, and they are composting more kitchen scraps. Local governments are setting up programs to divert trashed foods to livestock farmers. Some restaurants are reducing the size of their portions.One food saving principle that I found especially useful was the idea of accuracy in meal prep.
Blogs, such as Jonathan Bloom's at wastedfood.com, reveal consumers sounding off with anti-waste tips, such as learning to cook so that odds and ends in the refrigerator can be transformed into a meal rather than muck. And they complain about all-you-can-eat restaurants that throw out food rather than allow patrons to take home even a tiny amount of leftover.
How often does your family's leftovers get put into the fridge likely to never be seen again? What if, instead of that approach, the leftovers were minimized. Maybe even to the point that second servings weren't available.
Something important to think about.