Which like, this is arguably the sentiment the entire show is based around, since of course you should be afraid of the dark! you know what's out there and all, and Sam and Dean's lives are basically to receive as normal everything that shouldn't be. But while I also enjoy that, I think what really gets me is when the character offers their response and either doesn't realize the strangeness of their matter of factness, or only realizes belatedly that like, oh, that might raise questions that I don't care to answer, huh. (Versus the character being like, "Yup, ghosts are real. Knew this was coming, knew this was going to blow your mind. Next!")
Like, there's this scene in Cars 3 where Lightning McQueen makes this really quick joke about how life's a bitch and then you die--which you can sort of skim over on a first watch because you're not expecting that kind of thing from, well, Lightning McQueen. Who is 1) the Pixar protagonist of a PG-rated film about animated racecars, which is not really where nihilistic fatalism typically comes to roost, and 2) generally an upbeat, simple pleasures kind of guy, who doesn't tend to have a particularly strong grasp of his own spectrum of feelings, and doesn't often have the mental depth of field to think far enough in the future to be nihilistic about it.
But at the same time, he absolutely does have that side to him, and has across all three movies. The part of him that's dead serious, a little cynical, not that fun to be around, and utterly uncompromising. The part of him that understands, very much, the equally uncompromising and unsympathetic world he is a part of. I think in Cars 3 Lightning surprises even himself with that part of himself, and that's what I find so compelling about the joke. Because it's just a few scenes later where he's really like, Ohhhh, shit. That was weird of me, wasn't it. Oh wow. Which was helpful for him to realize for himself, but also drove home how alone he felt/how alone he genuinely was at that point in the film, because none of the other characters in that scene knew him well enough/felt brave enough to ask, "Are you okay?"