People seem to conveniently overlook the main arguments for why this supposed fine is idiotic, so I'll try once more summing this up as simply as possible:
- 50,000 downloads does not equal 50,000 lost sales. For all we know, Nintendo themselves downloaded it a ton to prop up the figure. We have absolutely no proof either way - if we did have a way of finding the people that downloaded the game, something tells me this guy wouldn't be taking all the blame in the first place.
- How likely is it that the people who download the game are potential customers at all? I'd say it's a very slim chance, because if they're downloading a game, they already have a modded Wii to begin with, and are either the type to pirate everything (cannot sell to this group), or wanted to play the game early before they buy it (these will buy the game either way).
Forget the "math," the 50,000 figure is useless. That number may as well be 1,000,000, it's irrelevant, because there's nothing we can calculate from it.