I think Nintendo has always been aimed at kids. This was necessary with the NES. The market needed this. They needed to start fresh. So, video games were, at that point, a kid's toy. That stigma has only started to change the last 1-2 decades. Possibly, starting with the Genesis, but definitely with the PSone and Saturn. Currently I have to remind myself that everyone plays video games. Hell, a lot of the girls I work with play video games as a main recreational hobby. Coming from my early 90s perspective; that's weird.
I actually would argue that Nintendo started the kid image. Atari was for everyone (well... nerds in the popular opinion). However, Nintendo was for kids. ROB, television commercials, and the general marketing are testament to that. The reported "short supply" of products technique is primarily used for kids toys (Cabbage Patch). Just compare the two commercials at the end of this post. I tried to pick representative commercials of the 80s marketing campaigns. (Nintendo has more adult commercials like Metroid, but the also have the Zelda is totally rad commercial). For comparison, just think if George Plimpton did NES commercials. But it worked for Intellivision.. quite well I might add.
This continues with the WiiU. Wonderful 101 is more adult than the Nintendo norm. But, keep in mind, it is a Platinum game. Wonderful 101 is Platinum's Wii friendly game. There is a lot of distance between Wonderful 101 and a more typical Platinum game such as Anarchy Reigns.
To sum everything up.... Nintendo: Your parents help you hook it up. There's a lot of assumptions in that statement.