I don't think Nintendo cares about whether warez loading is possible or not. They probably consider homebrew games (and emulation) to cause them lost revenue because people are playing them instead of buying games. It wouldn't surprise me.
It's pretty obvious that any games not officially approved by Ninty would be considered lost revenue, since after all their seal of quality pretty much means that the developer had to pay a nifty sum to them...
As I see it, they're always trying to keep the environment and possibilities of their consoles as closed as possible in order to maximize the income coming from it.