I think you've re-written history there. Amazon renegotiated with 4 of 5 publishers before iBooks even launched, so they were hardly frozen out, and Apple has never had much more than 10% of the eBook market, so they didn't 'corner the market' either.
Who do you think set the current standard price for ebooks at $9.99? Amazon. They had the monopoly of e-book market with the kindle so they got to dictate the price. Needless to say, publishers were not happy. The ten dollar price point for every ebook is scarcely profitable, so when Apple offered to sell their books at $12 to $15 they jumped at the offer. There's nothing unethical about being able to set prices on your own product and service. Amazon did the same thing, but their price was lower than Apple's, evidently that doesn't count as price fixing. Right. The notion that consumers are entitled to the lowest prices regardless of whether it is profitable for the individuals and corporations that produce the goods is dangerous. There are many sound reasons why Amazon is so utterly reviled by authors, publishers, and booksellers. They should not be allowed to have a monopoly on the ebook market.