Well based off the area, even Cherno wouldn't be that populated, maybe 25k at most like bilbo said. Also have to consider this virus or whatever could straight up kill some people, and that 10% may be a bad assumtion. Then consider people attempting to leave town to go to the military for protection, initial kills durring outbreak, etc. etc. The game also handles it by respawning Zeds, instead of just having some massive number being widdled away until server reset. As far as the shoot on site mentality, I honestly would if I was desperate enough. If I didn't have anything and you had a bag full of supplies, I'd definately consider taking you out. It just depends on the situation. Yes the game has become a little too deathmatchy, but it's still somewhat justifed. Edit: Even if it really is 10% fighting over remaining resources, they'd still be scarce. Durring the outbreak, people will get as much food as they can only to turn into zombies, so it would still be there, but in peoples bags and cars and what not. A lot of food isn't good for very long, and it's hard to get drinkable water without the pipeline running. Also in the situation where you bump into another guy at the super market, both looking for food, sure it's logical to think "I'll just check out the next one", but there's really no knowing if the next one isn't cleaned out already or if you'll have competition, or if you can even afford to be in town that long anyways. In the heat of things you'd shoot, grab, and gtfo.