I live near a recycling center, and every few weeks I drop by to deposit the accumulated detritus of Chez Buckley. In addition to the usual categories (cardboard, plastics by number, glass by color) there is a container set aside for books.
One day I looked in this container, and what did I see? Not just Yellow Pages and water-damaged paperbacks, but perfectly good novels and nonfiction! Lots of them, that people were just throwing away! I mean, throwing away for recycling, but still!
Although their prior owners considered them trash, it would still, technically, be considered stealing if I were to “rescue” these innocent books from their imminent destruction. And Stealing Is Wrong. So I most definitely did not liberate close to a hundred books and place them in my silver 2006 Honda Accord. I most certainly did not make a habit of checking the book bin every time I returned, nor did I chortle nefariously as I set free more and more shackled text. And I absolutely, unequivocally do not have over three hundred such books in my basement even now, arranged in tall piles by genre, which I encourage my friends to browse and pilfer every time they visit.
Tell you what, though: the first time I (ahem) didn’t do this, I figured nobody else would be crazy enough to do it, either. Turns out, book-stealing is a burgeoning vocation in our humble hamlet. Not just other patrons but the staff, too, enjoy getting their thief on. I have even, on one occasion, had a recycling worker tell me what delicious morsels were on offering today, to tempt me toward that dark indulgence. (I fled in white-faced horror, of course.)
I am constantly surprised to see how many people in our little town actually recycle, and even more surprised to see how many take books. I hear a lot about the death of print, the death of the novel, the Facebook generation and shrinking attention spans. And yeah, I do worry about people reading less. But I can tell you that where I live, there are plenty of folks who still care enough about books to go Robin Hood on a pile of trash.
And to those people, I say: shame on you. Because stealing is wrong.

This is funny enough that I am not going to shorten it, it deserves to spelled out in all its glory. Rolling on The Floor Laughing!
Haha, what what!!
I think the behavior you describe is a subset of two basic human psychological impulses: 1) a love of free crap, any crap, as long as it’s free; and 2) a fascination with other people’s garbage. For instance, I remember once leaving a three legged, cat-urine stained easy chair on the driveway one night, for pickup by the garbage men the following day, and finding it missing when I awoke in the morning.
I would try to argue, except that the bookshelf in my basement is also rescued trash.