SSBB can be played with wii mote only, Mario Kart too, NSMB too.
Brawl doesn't count -_- Then again, those who play it with four players probably use Gamecube controllers anyway.
I'm one of those who has four Wii remotes, which I sometimes use simultaneously for games like Guitar Hero, NSMB Wii, Just Dance (I have a big family...), etc. That said, I only have two nunchucks, and I've never needed more. I do prefer the Wii Remote and Nunchuck to the GC controller in Brawl, but most of my friends disagree.
It's nice to have the option of four-player, two-handed gaming, but so far I just haven't found necessary on Wii, and I doubt that will change much on the PS3. But Microsoft really does need to do something about their two-person limit. Sure, alternating could be fun, but simultaneous play is probably more so.
"Jesus said to him, 'I am the way, the truth, and the life. No one comes to the Father except through me.' " ~John 14:6 (NKJV)
