Why is Gohan's hair black if Chi-Chi's hair was Blue(manga)?

[Gaffer Tape]

I would never in a million years ever thought that was Chichi until someone on the forums mentioned it, and, with that said, I'm still not sure it's supposed to be her. I mean, it does resemble her in the face, but then again, most of Toriyama's faces look alike. The hair somewhat resembles Chichi's hair during the 23rd Tenkaichi Budoukai, but nowhere else in the series. But Chichi would never dress like that and the posturing is all wrong. Unless Toriyama was going for a purposely out of character "we're a biker gang" look (which would make Goku the odd one out as he looks just like regular ol' Goku) I still have a hard time believing that's Chichi.

[dbgtFO]

The illustration was made for chapter 187's title page, which is in the middle of Goku's fight with Piccolo at the 23rd Tournament(the colour chapter featuring Piccolo's giant form), so it was one of those, that had characters in situations we don't see them in that often.