Haha, go Kevin Butler.
Seriously, I think Nintendo wanted to see how well M+ was going to do before making it standard. WSR did better in Europe relative to Japan or the US so they got the black Wii and M+/WSR bundle first. It would be stupid to bundle M+ if it wasn't popular.
I think it's more to do with the ~30M units of M+ that have been sold rather than Kevin Butler.
Nov 2016 - NES outsells PS1 (JP)
Don't Play Stationary 4 ever. Switch!







