Well they might want that and I'm sure Sony wants a unique title from a big japanese franchise on the Vita but as it stands both Wii U and Vita aren't getting that. Capcom is a good example actually. They must be happy with the numbers of the MH3G HD, considering it's a port of a port. We'll see if we'll see more of the same with MH4 as well.
I suspect a MH4 Wii U port is in the works right now- if it does ok in the West I think it will come.
Pretty easy money for Capcom.