For Mario Kart I can kinda get Super was cause it was on the 'Super' Nintendo and cause all mario games at that point where 'Super' Mario 64 was cause all N64 games where literally 'Insert Name Here'64 Double Dash cause double the people per kart Wii cause console name 7 idk 8 cause it has a track shaped like a 8 for Luigi's Mansion, idk I think Nintendo thinks that us americans hate numbers and would rather have subtitles