One reason I think is that Japan likes Nintendo more than America does. Another thing is that I think here in North America, people are more likely to blindly support the system with better specs and write off the other system as a failure, without even considering the systems capabilities. This means "PS Vita is better in every way, 3DS sucks because the PS Vita is so much stronger and the PSP is probably stronger too." I've seen it everywhere and lots of people in person think that, too. This group may be relatively small in comparison to the whole community of gamers, but it definitely seems more prevalent here.
I also agree that localization of games should occur more often, as well as globalized releases that it seems Luigi's Mansion will be getting. I think those promote sales, as well as special bundles and designs for the 3DS.
