My aversion to shelved hardcopy books isn't really based on space considerations. It's a cleaning/dust factor. Shelves full of books need dusted way more often than I can find the time to do properly (taking all the books down, wiping both books and shelves). I work hard these days to make sure that the floor represents the largest combined horizontal surface in any room. The quickest way to ensure that I can quickly dust a room is to eliminate shelves (and their contents), extraneous furniture, and valances/curtains of any kind.
I want to spend my limited spare time reading books, not cleaning them.
