the argument fits here too.

Books In Defense of Amazon:

This isn’t the case with Amazon. Before it appeared on the scene, if you lived in a part of the country that happened not to be served by a great independent bookstore, you were out of luck when it came to getting books other than bestsellers. As a child growing up in suburban Baltimore—not exactly a backwater!—I felt keenly the lack of ready access to the books that I wanted. (Remember the joke of a selection at your local mall’s Waldenbooks?) And with the quirkier independents—such as the great Louie’s to which I paid tribute above—you were at the mercy of the owner’s idiosyncrasies, which meant that you might find shelves stocked with contemporary poetry but nothing by, say, Tolstoy.

This is a US article but the argument fits here too. Arguably Borders UK went out of business because they reduced their selection, removing one of their main selling points. Waterstones isn't looking pleased for some of the same reasons (not least changing the branch to branch individual buying process in favour central warehousing).

Amazon stock almost everything, and if they don't have it, one of the indies who are selling through their website will. I also like that about Amazon. It supports independent retailers by providing them with an infrastructure to offer their wares. And cheaper, although clearly that helps us rather than them.

I've also seen people criticising Lovefilm lately for putting the high street video rental shops out of business. But I don't see Blockbuster or the majority of those indies stocking the Tommy Trinder or Bunuel films I received this week; along with cheaper retail dvds, viewers seem to be happy to sacrifice immediate choice for selection and price. Or at least I am.