There is a lot of waste in the food supply chain. Some of that is suitable for human consumption at the point where it is classified as waste [1]. In Europe the food waste in fruit and vegetables is over 50% [2], of which at least half could be turned into black soldier fly or mealworm feed, which makes for good poultry or fish feed. But most of it today is going into waste dumps or at best turned into biogas.
Disclosure, I work for a startup that turns this into a circular food production system, from food waste, via insects to fish and vegetables via aquaponics.
[1] EU rules say eggs should be marked “Best before date” as 28 days after they have been laid, but stored propperly they are good for at least double that time. (Swedish) http://www.svenskaagg.se/?p=19895 In the UK supposedly 720 million eggs are thrown away each year. https://www.independent.co.uk/life-style/food-and-drink/eggs...
[2] http://www.fao.org/3/mb060e/mb060e00.htm