I don't exclusively read from my Kindle. I, like everyone else, still read analog books. For instance, I just finished reading Anansi Boys, by Neil Gaiman. It was my "work book", the book I keep at my desk to read during my lunch at work, and I was reading it in 15-20 minute spurts over a couple of weeks. The thing is, whenever anyone asked me what I was reading, all I had to do was turn the book over and show them the cover.
I realized this action just a few days ago. Everyone does it. You see someone reading, you say "Hey, whatcha got there?", and the reader turns the book to show you the cover. Sometimes they tell you the title and author when they do it. Sometimes you have to make the effort to read the information yourself. Either way, it's a universal thing, that showing of the cover.
A lot of attention is paid to book covers, whether the book is in print, or electronic. We judge books by their covers, that's just how we as humans work. But, if what someone comes up to me while I'm reading my Kindle, and they ask what I'm reading? I can't just show them the cover. I have to tell them, "Perdido Street Station."
"It's by China Mieville."
"What's it about?"
"It's about this city, and the people living in it. There are humans, and bug people, and bird people, and people who are a combination of man and machine. There's a scientist..." (Actually, I've just started reading this, so I really don't know the whole plot so I'm not going to get into it.) The point is, if I had the book in print, I could just show them the cover, and the inquisitor could get the title, author (and I wouldn't have to mumble my way through his name because I have no idea how to pronounce it), and possibly the genre of the book, and I wouldn't have to be bothered to speak to them.