One of the reasons I loved doing KP (kitchen patrol). Whatever wasn't used, we got to take home. At the time I had a stepmother who was a bit strict with what us "kids" were allowed to eat. Well, my little cartons of milk, my casseroles, my whatever...I can eat all I want (then she'd ask to have some of the milk for my baby sister; don't worry I didn't say no). I'd also use money I made to buy sherbet and eat that for breakfast. Whoa whoa, put the flamethrowers down...I was still in High School! Moved outta there as soon as I could.
Bit later I started working at Taco Bell. Lot of the "waste" went straight to our stomachs. Most food that was prepared but not used was put in plastic bags and in the fridge, then it was warmed up first thing the next morning.
My thoughts on wasting food have changed a bit over the years. Now, I'm mostly worried about wasting meat. Bastard I am, I don't care if a plant had to die just so I could toss it in the trash; but an animal, that's different.