First of all, just because you only read one book at a time, doesn't mean that other people are the same way. Second, even if you only read one book at a time

First of all, just because you only read one book at a time, doesn't mean that other people are the same way. Second, even if you only read one book at a time (like yourself, and me as well), an ereader like the Nook or Kindle is still significantly more compact than even a trade paperback. A 700+ page hardcover? Forget it, it's not even a contest.