Its probably a bit of an artist warp kind of deal. Even Akira Toriyama did it when you compare sprite work with some of his animated cutscenes.

Case in point:

Frog's human form Sprite
glenn_sprites.PNG

Cutscene Human Frog
HumanGlenn.jpg


I feel the character designer of CC just took some liberties and the team rolled with it. Hell, some fans wouldn't be surprised if it was purposely changed to troll CT fans since there is an underlying belief among some CC haters that CC's whole purpose was to basically deconstruct and brow beat CT due to Masato Kato being exasperated with creative differences during CT's development.