Mostly because people have fond memories of waking up one Christmas morning to find an N64 with a copy of SM64 and TLoZ:OoT, which ended up being their two favorite games ever. It was amazing. Nowadays, Mario games are very linear and repetitive, SM3DW being no exception. Although the multiplayer was a great addition and the game is great overall, fans like SM64 better because of the nostalgia. :)