There's just as much reason to not censor it as there is to censor it. None. Zero. Zilch.
You're wrong. There's exactly one reason to do that or to avoid it: whether they think they'll make more money if they make this change. If they think making that change will positively impact sales, they'll make it. If they think it'll negatively affect sales, they won't. End of story.
I don't know enough to know if this is the case here, but let's say they feel the Australian censorship boards will refuse to let them sell the game without changing it. That leaves them choosing whether to localize the game two ways, one for Australia, and one for everyone else, or just to alter the costumes for everybody outside of Japan and save some money.
Definitely this. It's the studio's (whether Nintendo or the developers) prerogative to make the change. What the hell can we do by this point? Money talks, and I'm sure they had "good reason"
(ie; whether it was for money, morals, or miscellaneous reasons) to do so.
Again, I'm not carrying a pitchfork around, but I definitely found the original designs a bit tasteless even if I'm not against censorship (but I definitely feel weird about it... I'm an Art History major, so I'm never to sure where to draw the line since the nudity in quite a lot of art throughout the centuries can feel just as pointless sometimes --- BUT IT'S 'ART'!!!!!! So: Nude or Prude, that is the question. :P ).
EDIT: Mmm Mmm...dem thighs
EDIT 2x: I just realized, despite the chubby and somewhat cutesy style for the artwork... the sprites have surprisingly small eyes. Amen.