This is a silly argument. If we use this kind logic than why dont we have safe zones, why not protect newbies and enact real punishments on players for PKing too much. This may be a game but that doesnt mean it cant or shouldnt try and make things somewhat realistic or natural.
My point is that using real life as an argument, as you did, is silly, because games are typically meant to be fun and provide a good environment consistent with designer choices. Arguing that videogames should be like real life can introduce a great many unnecessary complexities that do not necessarily benefit games.
Silly example: In real life, people not only need to eat, they also need to take the time to go to the bathroom. Would adding a "urinate on tree" option really enhance the game? It'd be more realistic, but it isn't necessary, adds complexity, and doesn't really enhance the game.
Bandit skins are poorly implement and even then create an unnatural and artificial divide between various players.
They create an artificial divide because the other player decided to kill fellow players. This enhances the experience for non-bandit players because it serves as a warning, and helps prevent the game from becoming deathmatch with zombies in the background, to an extent, I feel.
Again I am not a bandit, but say I decide a certain person I encounter is a danger to me, or they have some nice loot and I dont feel like theyll be that great a companion and I kill them, but then I encounter another person who I deem is more trustworthy or compatible with me and my survival. I cant approach that person or expect to be able to start off our relationship on equal footing because they have unnaturally been notified that I kill another player. And this is just an example of me willingly killing another player. Many people are bandits due to self defense and suffer for it.
This is a game about uncertainty, so why have a feature that distinctly labels certain players.
I think I understand what you are saying, but please consider it from a different perspective, and look at what you are asking for:
You want to be able to essentially grief people by PKing them, taking their stuff, farming respawning people, and so forth, and yet after all of that, be able to approach any such player with no negative effects at all.
That's nice for griefers and bandits, but not so nice for non-bandit players, self-defense excluded (especially since you seem to indicate that humanity can already be regained).