I'm 24, so I fit right in those demographics... Barely.
If I had an eReader when I was 16, it would have made my life easier. It makes my life easier now because it's easier to find quotations, it's easier to take notes within the ebooks themselves, and it's much easier on my hands and eyes.
They don't see it now, but they will in a few years.
I have space for books, but the only thing they do is collect dust, and annoy me because I have to wipe them down every few months.