Uneven relationship
It is easy for Amazon to give up revenue on books, they are only a small part of their overall revenue. Publishers are in business to sell books and only sell books. They don't sell TVs, candy, makeup, tires and cans of paint.
If Amazon was only a fraction of their sales, it wouldn't be a big deal, but Amazon accounts for nearly all their e-book sales, and e-books are increasing their overall share of the book market every year.
This is a shameless PR move by Amazon to try to make Hatchette look bad, but if the situation were reversed and forgoing this revenue would have the same relative effect on Amazon's bottom line as it would Hatchette's, they wouldn't even consider it.
Biting the hand that feeds IT
