Dont call me an idiot, please.
It was just a bit of light hearted fun. And now I will deliver my light hearted rebuttal:
1) Magus probably, being fabulously rich, was able to obtain lapis lazuli and mix it with charcoal to get the dark blue hair colour. That, or he had his own personal stash of hair dye that he carried around everywhere.
2) Give me a link, and I will believe you. I just looked it up and searched for quite a while and all I got was hair care and hair products. 'Blue dye to complement your natural hair colour' etc.
3) That doesnt mean a thing. It is possible to get permanent dyes; maybe QZ just got into a monthly dyeing routine in which she dyes the roots blue. Many people get into such a routine for thier whole lives, and think nothing of it. Secondly, blue hair could be a status symbol, akin to being of blue blood.... But blue haired...
4) If it WERE a status symbol of royalty, Schala may be breaking a taboo by not dying her hair. She could be forced out of the royal family, and eventually society. She is able to fight for equality from her position of power better than if she were just a common Zealian. Even if it is not a status symbol, Schala has feelings and moods like everyone else, and would most likely submit to peer pressure. She may have magical powers, but she isnt super human (I believe that everyone in CT has latent magical ability, that only has to be unlocked. Whether by Lavos or Spekkio, it doesnt matter.)
Another thing is this: if Schala were to keep her existing hair and not dye it blue, she wouldn't be equal to her peers anymore. There is my rebuttal.
Now I say only this: you have to be a little light hearted sometimes and not be so damn serious all the time. Lighten up!