Actually 9-10 year old boys in particular are crazy about the Playstation brand because they desperately want to be playing games their mom would say no to (ie: Grand Theft Auto).
Nintendo ironically while they do aim for kids, sure it doesn't surprise me that their actual fan base is mostly adults.
I've never seen a kid buying an Amiibo toy ... it's *always* 20-30 something males, lol.