Amazon ebook division was profitable so yes, there was money to he made.
I think Amazon was trying to woo people to their e-book reader by having 'affordable content', and take a loss on that content to move their high profit devices. It isn't necessarily illegal as many companies have done the same over the years with a wide variety of devices. What makes this awkward is that Apple tried to, apparently, 'support' the publishers by removing Amazon's ability to artificially lower the price of the content...
A noble gesture, but technically illegal. If my reading is correct, why the former tactic isn't illegal while the later is is rather baffling. But I guess it is legal for a corporation to take a loss, and illegal for them to boost their profits, which makes sense on a few levels...
But anyway...
I was 'gifted' a Kindle Fire HD7, and find it nearly unusable compared to the iPad. I don't know how to get it to be more usable. It seems to be very 'clunky', and not at all intuitive. Or maybe I'm spoiled...