The last time Nintendo really marketed to older teens/adults was the late 90s, early 2000s (in the US anyway) before Howard Lincoln/Minoru Arakawa left the company.
Conker was advertisied in Playboy Magazine:
https://www.youtube.com/watch?v=j9Qa08QQ4wg
They had swanky Cube Club parties to push the GameCube with a lot of celebrities and what not:
I think though after the GameCube failed to beat the XBox, MS kinda pushed Nintendo out of the core/core casual side of the market (too many mistakes made with the GameCube allowed even a newcomer like MS to beat Nintendo), Nintendo found themselves pushed out of that market. Playstation and XBox were "cool". GameCube was not.
Nintendo doesn't market like the above anymore, their marketing and focus today is much moreso on kids/families, unfortuantely kids aren't buying the Wii U either.
