Throwing my 2p in, there are two ore three points raised in the with the original post and some of the replys and ill chime in on the ones I can.
First the reselling of paper books. Which I do not generally resell my unwanted paper books nowadays, it is mainly because I mainly purchase only the books I'm pretty sure I'm going to keep.
I have resold books in the past, sometimes through Amazon, usually through a local used books store and while I've usually not gotten back much it was better then trashing them, and it did allow me to buy a few more new ones. My sister used to get a better deal as she usually got the store credit as the store had a good collection of her favourite genre's.
Having said that, having the freedom to sell or give away a copy can be quiet important, especially if you want to introduce a friend or relative to a genre or author and is something I miss at times with eBooks.
A Much more relevant problem for me (and I believe many others) is the restrictions imposed by DRM. I tend to change gadgets and computers regularly, and I'm wary of being dependent on a company's good graces to be able to access content I paid for. As such I've consciously made the choice to only buy books with DRM which has been cracked so that I can choose to remove it if I want or need to.
And Harry, I believe the analogy of comparing eBooks to Pizza is bit of a red herring. Ill actually compare it to the difference between buying a VHS tape / DVD and going to the Movies, where watching the Movie in the theatre is like the Pizza, a one time experience while Getting the DVD is getting a physical object and having the right to watch it when ever I want, or if I wished to giving it away. And As long as I Physically have it, I can still use it. Even if the company that made it goes out of business, i'm not going to lose the ability to use it.
For me ebooks are the equivalent of my DVD / Tapes (many of which I still watch after 20 years) and I still want to be able to access them in the future.