You have to force yourself to not speak to someone working at your local library when you see a beloved book of your childhood--a former quest book, no less--miscategorized into the YA section.
You also have to restrain yourself from passive-aggressively reshelving the book in the children's section.
And then you go home and search the consortium catalog to confirm your suspicion that every other library, presumably staffed by rational librarians, have this book in children's.Which they do. You're tempted to search WorldCat for further vindication, but you restrain yourself.
You yearn to check the circulation statistics and history of the book's categorization. But since you don't have access to the library's records, you resort to venting your righteous indignation to the world. You cling to the thought that it could be worse; you could theoretically be more nutty. At least you're not this guy. Or this guy: