My rule against buying donated tomes flipped after that St. Vinnie's trip

For about 3 years I swore I would never pick up ex-library copies because of the stamps and stickers ruining the covers. Last month my buddy dragged me into the St. Vincent de Paul on 4th Ave and there was this beat-up 1978 copy of 'The Name of the Rose' with a torn dust jacket and a due date card still in the pocket. I almost walked past it, but the checkout lady said 'this one's got the old map foldout inside, those are getting rare' and I flipped through it right there. That little extra piece, the yellowed foldout with the abbey layout, convinced me that the library marks are just history, not damage. I paid $1.50 for it and now I actually hunt for ex-library copies with the card pockets and processing stamps because they tell a story. Has anyone else had a specific physical detail in a used book change their whole stance on what they collect?