I guess 12 year olds are considered adult since they started calling books written for teens as young as that, 'young adult' for some reason.
That may be because a lot of adults like them too. In any case, books are different. There's a noticeable age overlap between kids who want toys and kids who read grown up books.
At 10 I stopped going to the kid's and teen's section of the library, and I was in the early years of my Playmo collection. At 12 I was reading gory, violent adult books and was saving up for a dollhouse.
I'm also not surprised, but can you really count 'board games' or 'video games' that are explicitly aimed at adults, and even arts and crafts kits as toys?
Yeah, I wouldn't count kits and games that are intended for adults.