Some legit developers will work ground up on Wii but a lot of ppl get lazy and the ones with the quick cash-in mentality taking advantage of the Wii's userbase for easy sales will just do it on the PS2 since they've been working on that for years and probably have both experience/better engine tools to work off of.
It's a shame since part of what's holding back the Wii is how it's not a massive leap from the GC spec wise. Which means developers who got used to the GC should be able to feel right at home with the Wii but then again the GC wasn't exactly known for massive third party support.







