I can't be the only person who actively inconveniences himself when reading to make sure my book spines stay clean of creases. By which I mean opening the book just enough to read it, even if that means sometimes needing to sit in awkward or uncomfortable positions for there to be enough light to read, particular the inner parts of the pages where there would otherwise be a shadow. It also makes buying used books difficult, as if the previous owner didn't take similar care of it, then I don't consider it to be in buyable condition.