I believe Amazon already does, but the future isn't an Amazon monolith controlling the entire vertical infrastructure.
The correct future is many printing businesses competing with each other, many logistics and shipping companies competing with each other, all separate and competing amongst themselves for the business of both content creators and content consumers. It doesn't work right if authors are 'vendor locked' into Amazon's printing and distribution network, it needs to be a many-to-many printers-to-distributors network with healthy competition for the "right future".
There are likely quite a few underutilized Espresso printers out there today. Just noticed that http://www.ondemandbooks.com/ is a search engine that links to the handful of stores which have a printer.
The correct future is many printing businesses competing with each other, many logistics and shipping companies competing with each other, all separate and competing amongst themselves for the business of both content creators and content consumers. It doesn't work right if authors are 'vendor locked' into Amazon's printing and distribution network, it needs to be a many-to-many printers-to-distributors network with healthy competition for the "right future".