Well, I'm not American, but I think the situation is similar in a lot of the developed world. In our household, nothing edible gets 'thrown away'. If we don't eat it, the dogs and cats get second pickings, if they don't want it, the hens get third options, if they don't eat it, it goes in the worm bin, and anything leftover goes onto the compost pile. The compost, chicken poo and worm castings all get dug back into the veggie garden to start the cycle over again. Sometimes we feed spare worms to the chickens, definitely one of their favourite treats. And of course, a lot of the spare veggies from the veggie patch, which were fertilised by the chicken waste, goes back to feed the hens again. We also use some of our spare cardboard to grow mushrooms.
However, I know for a fact we are in the minority, and that most of our neighbors throw away a great deal of potentially useful food scraps and garden 'waste'. But it could be worse. In our city, we have one of those separate rubbish bins for organic matter, which gets collected and taken away to be composted and re-sold to consumers that are too lazy to make their own.