I don't own and have no intention of buying one of the ebooks. I don't buy books either - only read each one once so I go to my local library and get them for free ... or might buy a used paperback to take on a cruise. My library gets the books (particularly the best sellers and authors I like) right away.
There's the initial cost of the ebook, then around $9-10 for most others and though I've never tried one (as in just holding it), I don't think it would be as comfortable to hold as a book. I have observed cruisers using them and they seem to enjoy - it's just my opinion. So all those $10 +, I can add to my cruise piggy bank!