I suspect lots of the "read-a-lot" people are just plain fast readers.

The only other solution I can suggest would be to get an ebook-reading gizmo that's a decent compromise between readability and pocket-portability—I use a Nokia 770—and stick the Baen versions of all your books on it. Carry it along with you and read it whenever you have a spare moment (standing in long lines, in the bathroom, etc.)