The dispute between Amazon and Hatchette is a fight between a retailer and a supplier. Same as Costco/Walmart and a manufacturer, or a broadcast network NBC with NFL football, or TV series production and an actor's contract renewal. All negotiating parties use whatever market leverage they have to get the most favorable terms possible.
Hatchette can still sell via B&N, iBooks, ebay, open their own e-commerce site, etc. Amazon's hardball tactics are not barring any of those options for the book publisher.
[1]http://www.barnesandnoble.com/s/j-k-rowling?store=allproduct... [2]http://www.apple.com/ibooks/
Walmart, of course, being notorious for using its huge market position to force costs onto suppliers. That's part of how it gets the low prices: because if you sell at retail, and you don't agree your product should costs what Walmart thinks it should cost, you find yourself locked out of a giant part of the economy.
That's what they do. If you aren't willing to sell at the lowest price possible, you need to be in a different market.
Neither they nor their customers owe you a certain profit margin.
Source: http://www.publishersweekly.com/pw/by-topic/digital/retailin...
Sure, but monopoly is by market, and if online vs. physical retail of books really is a distinct market (as, incidentally, you present it here) by the test applied in antitrust analysis (which I suspect it may well be), then the fact that there is also a physical book retail market that Amazon has none of would not be relevant, and combining the two markets to get a overall book spending market share would not be meaningful.
Certainly there are other online book vendors around? Maybe I'm living in another world ...
As a side note, you should probably check Amazon.ca where you have free shipment for Canada for order over $25.
http://www.abebooks.com/books/CompanyInformation/?cm_sp=Ftr-...
I'm sure if I spent an hour or two finding the lowest price on 20-30 items I could save a bit of money on the order(s), but I don't think it's really worth my time for my default use case.
Now, if I were looking at items like text books or reference books, I would likely do the research. Such materials are often sold at huge variation in price across retailers ...
For reference books you should definitely check alternative sellers, I've seen programming books priced at $120 in Canadian bookstore at $20 (or less for the international edition).
The DOJ went after Apple over ebooks, but the reasoning for that was sort of the opposite of this situation. Apple was colluding with publishers to keep prices high, thus (arguably) exerting excessive market influence through their combined weight. This is a dispute between Amazon and a publisher, which is (somewhat arguably) exactly what should happen in the marketplace. When the supply chain colludes, their power increases. When they contend, their individual powers are kept in check.
Both collusion between players in a market (the publishers in the Apple case, Apple's role was as a deliberate collaborator in that illegal collusion) and unilateral action by one player with market power are prohibited by antitrust rules.
So, yes, while they are in a sense "opposite", both collusion of the Apple/Publishers sort and unilateral action by a dominant player (as in, e.g., the big Microsoft antitrust case, and arguable Amazon in this case) can violate antitrust law.