My first thought is how accessible these books are. If a book hasn't been checked out in years, and there's another library in the interlibrary loan network that has a copy, there's no practical reason to keep another copy. If you can request a book and have it arrive in a few days, that's not an issue in any real sense, especially for books that nobody is checking out in the first place. I used to work in a library,…
This is hardly comparable to difficult philosophy books as mentioned in the article, though. To my mind, the poin of libraries is to house and make accessible difficult or challenging books that might not necessarily be popular. I was shocked when I first visited an American library and found large numbers of mass-market paperbacks and magazines. When I say 'large numbers' I mean 10 or 20 copies of books by Oprah or other celebrity authors. Librarians would have it that they're serving the community by making these books available in the library around the same time they're available in bookstores, ignoring the fact that once the publisher's marketing drive is over all those extra copies are going to be surplus. I do not understand why you would buy 20 copies of one book when you could have it and 19 other books.