Amazon Just Doesn't Care for Content Providers
Amazon has a unique paradigm. They create a marketplace and then invite the public to contribute content to their marketplace. I am an Android developer (as well as an Apple developer) and I get regular emails from Amazon harassing me to upload my apps to the Amazon store.
Amazon also makes the Kindle which is a dedicated eReader. They created a self-publishing platform where any Tom, Dick or Harry can sell their books to the public directly. They also created a community forum for these same people to connect with one another to solve their publishing issues.
It was a masterful stroke, because with the forum, they no longer needed a support line at Amazon. Other users would answer the questions. It is a prime example of maximizing the profits while minimizing the expenses.
However, in the minimizing their expenses department, the forum moderators do not even visit every day. Hence when the robo-spammers attack, the forums are filled with link farms, link spam and crap. It takes days for the moderator (probably an intern) to notice and clean out the spam.
Amazon certainly knows how to save a buck.
As for me, I think that the reason is that Amazon knows that dedicated hardware to read books is on the way out with the new tablets coming online. Still, they should show a measure of respect for the content providers that made them millions.