You're thinking TOOOOOOOOOOOO MUCH! The author is writing from the point of view of a typical dumb high school boy who think about girl in that way...not from a girl or the author point of view. Beside, this is 'A WORK OF FICTION.'
Calm down and don't blame it on the author. Even in the west there's this idea that scarring a woman's face is worse than if it's a guy. And that women should not have scars on their faces, I mean just look at the makeup industry. Therefore, since Yuki is not a girl he doesn't think having a scar on his face is such a big deal.
I honestly don't see how you translated what was happening on page 27 as "girls being dumb" that's not even what's being said!
I feel like you took this a little overboard. I agree fully with the two above me and being a girl myself I don't really find it offensive since it is in fact a work of fiction and done from the perspective of a high school boy. This also isn't the first time for a manga to state something along these lines before. Not to mention that the statement could go both ways. Not all boys are fine with facial scars. Anyways, the fact of the matter is that you took this a little too hard for a subject that doesn't really raise any sort of solid offense. x'DD
getting angry for no reason which is true in some cases but is a rather rash generalization. On chapter 1 27/36 I just heard something absolutely ridiculous. Sure there are girls who care if there are scars on their faces but there are also normal girls that don't care at all about what others think about what they look like. With that kind of comment, there's this feeling that the author is generalizing that all girls are dumbasses or just follow other people without the ability to think for themselves which is kind of reinforcing a negative stereotype.