With Amazon's notorious history of locking up / wiping devices in name of DRM (ref 1, ref2) , I wouldn't be surprised if people would prefer pushing it directly to kindle instead of through Amazon. (Atleast one layer scrutiny is avoided).

That said, this looks pretty clean.

Ref 1: http://www.theguardian.com/money/2012/oct/22/amazon-wipes-cu...

Ref 2: http://boingboing.net/2009/07/30/high-school-student-1.html