76,000 sales for a game of that scope and ambition is perfectly fine.
The team already had the art pipeline sorted, the game's design already done and they probably reused assets.

76,000 * $40 is about three million dollars in total revenue, and to be honest: I doubt the game's development budget was over one million dollars.

The game will continue to sell and Nintendo gets to put its footage in trailers and such; the game is a success.