What you fail to realize is that Nintendo had been thinking about Wii games and doing research on what direction they wanted to go, and really, they blind-sided the 3rd parties. Third parties were like, "what the shit are we supposed to do? What kind of games are we suposed to make? What's going to sell?".
This is the major difference.
Games sell on the vita, and developers know what gamers want to play.
Also, thank you for gathering all the SCE sales for the first five days of sales, I was looking for a quick resource for that.