Because enlightenment is not the release/death of the ego - ego death is ego itself but many enlightened people tend not to understand that as they'd prefer to think of themselves as enlightened. If you really want to understand what enlightenment really means to people look to mentality not Spirituality.

What does enlightenment mean to you and what are the reasons you think you'll be better off if you were enlightened? When you answer those questions you'll understand all you need to know.