I find ereaders convenient in that people cannot "investigate" what I am reading... which for some reason, everyone always seems to be fascinated about what book I am reading!
It tends to interrupt, you know, the "reading" part.
(Obviously that is not my only reason for using an ereader. It isn't even one of the main reasons.)
Clearly I don't actually care if they know what I am reading
because I have the screensaver of my Kindle set to display the cover of whichever book I am in the middle of reading.