Because I believe strongly that coloring books stunt creative growth and increase passivity. I allow my son to add color to his own line drawings, paint, etc., but the forms all come from him.
I don't decide what to give my kid just on the basis of what appeals to him. Lots of kids like playing shoot-'em-up video games. Some people like smoking crack. I'm just sayin'.
As coloring books go, the one to which you linked is not bad. I will probably never buy it for my son, but I will allow that it is not the sort of thing I'm really concerned about either. If those sorts of subjects were often seen in coloring books, I wouldn't have such a problem with them. I have also seen some other ones that aren't in the "He-Man vs. Skeletor Battle for the Universe" vein: mandalas and other geometric designs, etc. In the end, I think it best to just condition him to avoid them.
I doubt that anyone near me here in New Hampshire, within the school system or without, would offer a random kid a coloring book like the one you've pointed out. My kid will continue to be instructed to firmly refuse if he's offered a coloring book by anyone when I'm not there. If it's a good one, I might consider it.
