Seems like a reasonable conjecture. If this is the case, I wish they'd give in and support ePub and make side-loading a bit easier so that books purchased else

Seems like a reasonable conjecture. If this is the case, I wish they'd give in and support ePub and make side-loading a bit easier so that books purchased elsewhere could be added to your Kindle. I'd love an ultimate-eInk-reader device that supported everything from everywhere. (Yes, I have Calibre. It's way too tedious for most people.)