When you deal with amazon you have two choices. You can sell them your book at a 50% discount or a 55% discount. So with a book like campiglia's, you really have to print about a million of them to break even on printing and shipping, because you have to ship them to amazon, (and pay for them to be shipped to you from China) which again isn't cheap for that book.

I'm not sure how they do free shipping, probably incorporated into the discounts they get for allowing you to sell your book through them. B and N is the worst company, I actually took my book off their site because it was too much of a hassle and more of a discount.

This is how it works for self publishers or independent publishers. Similar for big time publishers, but they work in bulk books and they get better breaks on the discount, not much, but better.