Your last two points resonate.

Whatever book I'm currently reading gets carried around with me quite a bit. It's thrown (and left) in the car, on my desk at work. It is not exceptionally well taken care of. It's just a cheap paperback, in most cases; losing it won't matter much. There's a kind of cognitive tax to carrying around something you don't want to lose or have to be careful with.

Besides, I can only read one book at a time, so the ability to access any book other than the one I'm currently reading doesn't offer much value.