Originally Posted by S.Canton
I'm probably repeating what others have said, but the reason for the lack of page numbers is that page/font sizes are not fixed, which would make it impossible. I think the current system is pretty intuitive, but I know there are people who don't particularly like it.
It doesn't make it impossible (the Sony reader does it), just variable. As someone already commented, it means the page numbers have to be recalculated every time you change the type size. I prefer the Kindle method in which the location numbers are, to use a math term, invariant under transformation.