Normies do believe in survival of the fittest, they laugh at the socially awkward guy just trying to fit in and make friends and go out of their way to act like he is stupid and a bad person for petty reasons and exclude him. They just don't need to explain it with abstractions and turn it into some kind of philosophy, they just do it out of trial and error and years and years of social experience in the demonic normy hive. They just think "oh, it's one of those guys, I don't have time for him, let's get rid of him".
Then you have all these fedoras who only realize the darwinian struggle in their late teens or early adulthood, and they think it is an epiphany and take themselves too seriously and read too much into it as though they will uncover more cardinal truths about the world and learn to fix their predicament. But at heart these are nice guys, they are cooperative and friendly, if they do anything edgy they have to think about it a lot and plan it ahead and it is usually limited and doesn't accomplish anything.