It's a shame to see what some (not all) modern libraries do to the books they no longer want as part of their collections. To be clear, I have no problem with institutions removing outdated or under-circulated books. That's an important part of keeping the collection fresh and manageable.
But some libraries go a bit overboard when saying goodbye to an old book. I've seen oversized DISCARD stamps used multiple times within the same volume. I've seen pages defaced with thick black markers. I've seen where the circulation-card pocket was torn from the book, leaving a damaged page at best and sometimes a page torn in half.
There were classier ways once.
I smiled when I came across this blue, four-inch label that was pasted to the inside front cover of a discarded book from Bowdoin College in Maine many decades ago. The slim volume is 1874's Three and Four Place Tables of Logarithmic and Trionometric Functions by James Mills Peirce.1
No ugly stamps. No black markers. No torn pages.
In fact, one could argue that the book is a more interesting historical artifact with this label indicating part of its provenance.
Perhaps we shouldn't care what future generations will think about our treatment of books. But they will be judging us.
1. Don't laugh. Back in 1874, this book made Buzzfeed's list of "Ten Math Books That Your Children Will Absolutely Love Better Than Churning Butter."