The only foreseeable advantage I see, other than making us nuts (which while fun, probably doesn't help
amazon's bottom dollar), is to grow more home - grown kindle authors and to have more people buy into Author Central, thereby, in the end, making for lower
ebook prices (which equals more
units sold) and no traditional publisher middle man.
The point is the cost to the publisher is not fixed (the cost per
unit in royalties to the author, creation costs of the
ebook etc) but
amazon wants to pay a fixed price