I mean, the games we have up on here are also books; RPG books. They're both "physical games" and "books", if you define them by their form. If you use the stricter definition offered for the book category on itch, e.g., "tells a story" it's a bit muddier.
At this point I've also got, like, dozens and dozens of entries, so it'd be some work to go through and recategorize them all...