Maybe it's because the story isn't the point. I mean they are barely trying to put a story (SMG and Pikmin but not Zelda because the story in Zelda is deep and complex as all the games are connected).
In other games, they try to push a stupid story to you. For example, the story in Soul Calibur is so stupid it's no wonder it loses points there.
How many cups of darkness have I drank over the years? Even I don't know...







