> They are easier to read, store, and move.
I have the opposite experience in every category.
Read: For reading, I much prefer hardcover. The print is generally larger, and the book doesn't usually just collapse in on itself. (Sometimes a hardcover will be too stiff, but unless I'm willing to break the spine, a paperback is always 'stiff' in this sense.) I can't read fiction as easily in bed with a hardcover, although it's doable (and this is exactly why I've replaced paperback with the kindle version anyway).
Store: You can certainly store more paperbacks in the same space, but in my experience, it's messier and can quickly become unmanageable. I'm a big believer in quality over quantity. My library shelves are full. When new books come in, old books go out. The limited space makes me be more critical about which books I buy and which books I keep. That they're essentially all hardcover means I can literally see every book I own without getting up from my desk. They're all easy to access - just pull them right off the shelf. If I had less space, I think I'd rather have less books.
Move: I gave up on paperbacks because I was moving every six months or less for a period of about six years. Having these large boxes of books that I kept mostly 'just because' became tedious. I eventually just gave them all away. Granted, having an equivalent weight of hardcover would have been just as tedious, but they'd likely have had more value to me. Most of those paperbacks I would never have read again.
> Do people really throw away paperbacks?
I'll throw away hardcovers if I can't find another home for them. It's uncommon, but it happens.
This book really changed my relationship with books: https://en.wikipedia.org/wiki/How_to_Read_a_Book
It taught me to have expectations of books beyond just asking myself, 'Do I like this or not?.' It's mostly for reading non-fiction, but it's useful for fiction too.
Along with that change, I also decided if a book is worth owning a personal, physical copy of, it's worth making sure that copy is high quality.