We have saved a lot of money by not going into the grocery store but checking out the back first. Some of the bigger chains use so called 'compacters', sealed garbage containers that squeeze everything together. Those are obviously no good for us. Except from those and one or two unfriendly shopkeepers American consumerism has proven to be to our advantage, everywhere. The pictures below will give you an idea of the 'spoils' we've come across.
As a reminder: we are no thieves, everything you see has been discarded and thrown in the trash.