They don't leave or appear to be as shocked by the first sacrifices as most normal members of the audience would. I think is a lot to ask from us at that point, and it's probably a miscalculation where internal character logic (meaning showing us who these characters are by their actions regarding that moment) was privileged over basic narrative logic. They witness a pretty fucked up thing, by any standard, and next thing you know, no one seems to care that much about it. It's one thing for Dani, who is having an assimilation of her own with all of this, to digest it in a strange way; but it's completely different when our other three main characters just blow it off as "cultural". It seems unearned how barely two minutes after this very violent and traumatic moment, Christian and this other dude are discussing who has priority about their subject for a thesis. It really is like, "what the fuck? Shouldn't they be discussing something else right now? How come they don't say this to his other friend who wasn't there? How come that is not THE SUBJECT OF EVERY CONVERSATION FOR THE REST OF THE DAY, AT LEAST?
The scene with Dani by the lake seems like a better moment to follow the sacrifice, because this is when she expresses not only her concerns, but ours as well. The fact that she talks about this, expresses doubts, and maintains a logical position, frees us to let the subject go as well. But where the scene is at right now it comes a bit late, the damage is done and it becomes really difficult to "be" with these guys for a while. Nevertheless, it speaks of the film's power that it eventually can make us forget that (at least some of us) and get into the full experience of what comes next.
