I don't dispute anything in your first paragraph. The ability to preserve and distribute rare or unique documents and photos is amazing.
I'm not talking about rare books and antiquities, though. I'm talking about something far more common and mundane, and (to me at least) far more special.
The books I've inherited from my grandfather are not precious or valuable to anyone but me. They're precious because I know I'm touching the pages he touched, and when I come across the notes he's made in the margins, they're in his hand, written with the pen I remember watching him use when I was a child.
Most of us can't afford to spend hundreds or thousands of dollars on rare books. But most of us can afford a couple dollars for a paperback at the used book store—even those of us who can't spend the $80-$200 that the OP calls "cheap" for a Kindle.
This is one of the reasons I like ebooks for their convenience and ability to be widely distributed, but I would be devastated to see them replace bound books as the only choice.
We're seeing the way that movie and music companies are eager to trample over consumers in the name of protecting their copyrights. Do we really want to turn books into something that can only be read if you have the right device to display them? I don't trust Amazon, Apple, or anyone else to be the gatekeeper of my books. I want the ability to turn my back on them if they start editing, deleting, or censoring books. I want to be able to say "fine, then, I'll just go to the store and get a real book, and your Kindle can suck it."
Some of my worries seem almost silly today, but we've seen too many things go from far-fetched to reality in a generation or less.