> There has to be a reason why they are so nonchalant about it as well.

The reason is that this is the "casual guro" genre. Treating death casually is what you do in it. Stop assigning some meta meaning to it which isn't there.

Or would you also ask for a reason why everyone is always horny in porn? Or a reason why everyone constantly gets in funny situations in comedy? Oh, bUt tHeRe HAs tO bE a rEAsOn!