It was just a side game Nintendo showed at there conference and than showed a big first or third party game, people are just hating on this game because it was Nintendo's big surprise at E3 and not Retro's game.
Absolutely. I think most people are not really opposed to Nintendo making a minigame collection that gives an overview over many different usages of the Wii U controller. Making it in the form of a Nintendo theme park is actually a really nice idea.
The thing is, to most gamers this (or any minigame collection) isn't something big, and something big was needed because people saw Pikmin and Mario coming from a mile away.