Well, Jon, we part ways once again on style of ebooks
. I like having headers and/or footers. I tend to read 4 to 6 books at a time and I like the reminders the headers and/or footers provide. It isn't critical, but nice.
As for the "wasted" space, beauty is in the eye of the beholder and I prefer ebooks with more space between elements. I find them easier to read, especially as I (and my eyes) get older. A few extra pixels doesn't hurt.