They have differently shaped faces, though. Of course, it could be more different, but it's not like there is zero differences. Once you get used to seeing faces in hijabs, it's easy to tell the differences.
Yeah, I think there's more variation in the fine details of the faces than people are giving credit for, though it's not always easy to judge - the art style tends to keep the details to a minimum outside any relatively close up perspectives, and when you're used to picking the differences between characters based on things like hairstyle (which is
very common in manga) it's not always easy to refocus on other details.
The thing that did throw me a bit was the fact that the hijabs themselves all looked very very similar - not just the colour but the arrangement and the details as well. It almost looked unnatural - almost but not quite like a cut and paste job.
Though I think that's actually understandable in the context of the story - this is likely to be the first time any of them has worn a hijab, and I imagine they had someone come and give instructions, so basically everyone will be following that set of instructions and resulting in only small variations. And you'd probably need to have insane self-confidence to play around with the way your hijab was tied when you were on your first visit to an Islamic country and everyone around you was following along with the instructions . . . Though I'm a tiny bit disappointed that the author didn't have Tsubaki take the lead a bit - she's visited the Maldives before, enough to have ideas for a perfect makeout spot, it wouldn't be surprising if she already had experience with wearing a hijab and had her own sense of style and individuality . . . I mean, it's very far from the focus of the story, but it's the kind of thing that would be in character for her.
