I have noticed that many of the books that interest him are recommended for ages 8-12 (I'm sometimes tempted to lie to librarians that I'm getting books for his "older brother"), but still, this seems crazy.
I wouldn't worry about. DS6 goes to the librarian and asks for guidance now. The first time he did, he asked the kid's librarian for help finding a history book. She marched him over to the kid's history section, and she asked him what kind of history he wanted to read. Surprising everyone, he said Japanese history; without batting an eye, she took DS6 (DS5 then) to the normal library section and showed him where they were - explained a little dewey decimal, etc. I was embarrassed at first, sure she would think I prompted that, but she said, "you never know what they will find interesting...just let him be." A lovely experience, really.
