Well, this is not a pure coop game, but its not pure PvP either. It's about survival and my first advice would be: don't trust anyone. That being said I don't share the same experience as OP. I have meet many friendlies, even in cherno and elektro, probably more than I have meet bandits and PKers. Some I have teamed up with, but mostly I have just shared a few momenents with them before moving on. There are those out there who kill for fun (bandits), some for supplies and some to be safe themselves. Once I meet a survivor in cherno general store, he immediately opened fire with his marakov. I panicked, shot him a few times, and ran around a corner. From there I told him that I would leave him alone if he left me alone. He said he was sorry, he had bad experience with other players and wanted to defend himself. We healed up, had a chat, and went on in different directions. I never kill another survivor, even if he is out to kill me. The reason is that I never want that bandit skin. My mission in-game is to hunt bandits, I can't be one of them myself. There is actually a very interesting art to survive other bloodthirsty survivors when you are not allowed to kill them yourself. All i can say is always make sure your are not spottet first. Hail the other survivor by name and ask if he is friendly. If you are social about it you lessen the chance of him wanting to kill you, everyone enjoys a good conversation. People in survivor skin have never killed another survivor before, why would they start now? If you see a bandit; run or shoot! Also, don't just run into a building and begin looting it. Be smart about your movement and remember its okay to skip a good loot if you think it's too dangerous.