Our post office has a shipping discount, where you get 10% off all of your shipments you've sent during the month if you send 1000 packages or more. Once you ge

Our post office has a shipping discount, where you get 10% off all of your shipments you've sent during the month if you send 1000 packages or more. Once you get near this limit, you get into the perverse situation where it makes sense to send empty packages to nowhere.