Here is an understandable rant of mine: when visiting the bookstore to view its manga offerings, I was disappointed that I couldn't buy some titles because of their condition. Whether a book was bent out of shape from being read by too many non-paying hoodlums, or simply the paper was yellowing due to being exposed in constant fluorescent lighting, I couldn't bring myself to pay for such shoddy product.
The lighting is unavoidable, but I still can't buy a title that was printed before January 2008 just because the paper (on the surface of the top of the book) is yellow because it has been sitting under that blazing light for a long time! Eew! What do I do? Buy at a comic shop? Maybe. The lighting is darker in comic shops (and the books are cheaper, too!) I have been lucky with a certain comic shop that lets the women do the stocking and filing. These books just need tender care.
Consider this message in warning, beware of the books you find at major bookstores. They could have been handled several times a day by who knows? And the the paper yellows very fast. If it's not a new release, it belongs in the "NO" pile. I don't think the idea of selling manga in chill dark rooms is gonna fly, so I suggest you think twice before picking up that swiftly-aged tome.