Crazy book pricing doesn't make sense

Book pricing seems to be all over the place and I frequently come across crazy examples that seem to defy logic. For example, I was reading how Steven Spielberg's Robopocalypse is to be postponed indefinitely. It was to be a sci-fi movie based on the Robopocalypse book by Daniel H. Wilson. I haven't read the book, but if it is so good that people are thinking of spending tens of millions of dollars making a movie from it, I though that perhaps it might be worth reading. I thought I would head over to Amazon and check out the price. Here it is:

So Amazon is selling the book for £3.84 with free postage. It looks like a bargain to me. Look below and the Kindle Edition is £4.99. How on earth can an electronic edition of a book, which after all, is just a file on a computer, cost more than a physical book made of paper and ink and having distribution and delivery costs? That doesn't make sense to me.

Even cheaper is the used paperback edition, which looks an even better bargain at £1.28. Click the link though, and it is revealed that the postage is £2.80, making the total price for the used edition £4.08. So it costs more for the second hand edition than a brand spanking new copy from Amazon.

Let's focus on the Amazon Kindle and Amazon paperback. Not only is the paper edition cheaper, I can sell it second hand, on eBay for example, after I have read it. It appears to be worth at least £1.28. If I sell it after reading it I will recoup £1.28 of the initial cost, making a net cost of £2.56 for the paper edition compared to the £4.99 Kindle edition.

Does all this make sense to anyone? It doesn't to me. Needless to say I won't be buying the ebook or the second hand edition. It's weird when you can cut down trees, drag them to a lumber mill, grind them up into paper, print on it and then transport the book hundreds of miles for less than it costs to copy a file from Amazon's server to my ebook reader over the internet.