Unfortunately, those direct mailers are the U.S. Postal Service's customers. There is a rather inflammatory statement from the Postmaster General in the story

Unfortunately, those direct mailers are the U.S. Postal Service's customers. There is a rather inflammatory statement from the Postmaster General in the story about the demise of Outbox. “You mentioned making the service better for our customers; but the American citizens aren’t our customers—about 400 junk mailers are our customers. Your service hurts our ability to serve those customers.” http://www.insidesources.com/outbox-vs-usps-how-the-post-office-killed-digital-mail/ http://www.insidesources.com/outbox-vs-usps-how-the-post-off...