I mean you are comparing a show about zombies to a show about drugs/sex. Im not sure if its cultural difference or just the subject matter.A lot of it is sexuality. A bunch of Euphoria episodes seem to center around big parties or other venues that lend themselves to provocative behavior. No one bats an eye at bathroom sex or open drug use. I'm not saying that this is a realistic portrayal.
All of Us Are Dead is definitely not a show exploring teen sexuality but the cultural differences are on display nonetheless. The girls do wear short skirts but almost invariably with gym shorts or even sweats on underneath. And if a couple so much as holds hands, others in the group stare wide-eyed at the open display of affection.
I don't want to make very much of all this, it was just really interesting to me while watching both shows.