Makes perfect sense. I wouldn't have thought of any of those.

The only problem with the free-market point of view on this particular issue is that Amazon is omnipotent and controls such a huge market share. It's similar to the case with Wal Mart. Several recording artists were hurt badly when Wal Mart took their albums off the shelves for similar reasons (controversial content), effectively cutting a staggering number of consumers off from the artists since Wal Mart was the only distribution channel they bought their music through. Many people get their books solely through Amazon, and a competing site with access to books deemed inappropriate by Amazon may not be able to offer those books for such low prices (vis a vis economy of scale) thus controlling the literature that many people are exposed to. of course, they could just suck it up and get a library card...