Wow - where to start? It always puzzles me that people who are not interested in a certain technology seem to need to prove that their way is better, with thinly veiled snipes at those who choose to invest in the technology. I have several friends who are "what's the point" types, too - it's as unpleasant to hear in person as it is to read online.
For the record, at least two of my most die-hard "never, ever read from an electronic device" friends now have their own Kindles and you would think they were invented specifically for them lol.
As to your question, the first point I'd make is that not everybody chooses the same set of requirements you do for selecting your reading material. Not everyone needs or wants to buy used books, resell them, etc. Some people like to read new hardback books (which are almost always cheaper in ebook form). Some people like to keep the books they have purchased to reread them.
I think ereaders are wonderful inventions. I can see or hear about a book, search for and download it immediately, and be reading in less than a minute. I can store an endless number of books on
Amazon's servers (I have Kindle products) and move anything back and forth when I choose. I can enlarge the font size, change the background color (on the new Fire), have the book read out loud to me (if the publisher allows it), lend a book to another Kindle owner (again if the publisher allows it), check out a digital book from the public library, send a book as a gift to a friend and have it delivered immediately to her account, look up an unfamiliar word and have it defined for me immediately on the same page, search for a word or phrase and locate it immediately from the entire book...shoud I keep going?
Do you have shelves of books overflowing in your house? Always needing to buy more bookshelves? Not me - I have weeded my paper book collection down to fit the available shelving I already have. Everything else is in ebook form. If I want to buy something in paper to keep forever in that format, guess what? I do!!! Because there is no law that says I have to choose one or the other - I can have ebooks and paper books at the same time. In fact, for some favorites I have both!!
In short, there are many, many features of current ereaders that have nothing to do with money. In addition, there are thousands and thousands of free books and lots of opportunities to save, share and buy cheaply. Current bestsellers are never going to be cheap - in any format.
As to your point about the airplane, I've never been on a flight that made me turn off my Kindle for 30 minutes on each end of the flight. Five minutes, maybe. For those times I take a paper magazine or do some needlwork. If I so chose, I could also have a paper book for flight restricted reading times. The possibilities are endless.