I used to keep all the paper back books I bought, not so much for collecting but with an eye to re-reading them. I was a voracious reader 25 years ago. It was nothing for me to go through 200 books a year. Well when it came time to move and you have just packed 15 paper grocery bags of paper back books, it is pretty hard to justify keeping them with a thought of re-reading. So they all got given to the person that helped me move. They were a reader also, and had connections with a used book store.
Then the Kindle came along, just in time as I was getting priced out of paper back books, the Kindle was fine for a while but then the good free or very cheap $0.99 cent books slowly got priced out of my reach, but that was okay, because then my wife told me about Hive, so I became a reader and commenter on Hive.
RE: Value thrown away and a little gained