There are some who claim that life in the zone has reverted to "the law of the jungle" - kill or be killed. However, the truth may be a bit different.
Now as I see it, there are two types of people that maintain this social Darwinist mindset. Brigands seek to justify their actions with a "him or me" attitude. Settlement leaders lose their power base of people feel free to rely on themselves or walk off. Everyone else has a vested interest in not making enemies, and well - a reputation as a sociopath isn't exactly making friends.
I've had a few close calls. If it wasn't for pockets of bullet stopping gel sewn into this load bearing vest, I'd be dead four or five times over. However, that is because I go looking for trouble. Most people don't need military grade flexible armor, or even obsolescent Kevlar. There are plenty of non-violent ways to make a living in the zone.
For example - a lot of places want couriers. Signals propagate only so far without repeater stations, cables, or satellites. Working alone or in small groups or even alone and avoiding other contact is the best way to do that. Manual labor will keep you fed - replacing the aforementioned cables and repeaters can do a person well. Caravans are a little more dangerous, but often have the strength in numbers to mitigate anything too bad.
For that matter, not every foray into the zone is an epic search for the last V8 Interceptor, 200 Gauss rifles, and the spear of Longinus. There is profit to be had in the little stuff too. Un-rotted teddy bears for children, a back up drive with wedding photos, discographies of certain bands - quite a few people want their comforting reminders of the old days.
Even if you're unwilling to settle for a lesser take, don't fall to a mind set based on rationalization. Sure, if you're like me and hunting big jack-pots, you're going to run into some competition. But news gets around. And if it doesn't - well, a good working relationship can help - who wants to miss our on a great find because they made an enemy of the only one with a map. And of course - never underestimate alliances of convenience. One fifth of a take is better than being unable to recover anything at all.