Everybody loves a good troll. You will rebel against some rules over the internet and show the dayz forums how cool you are. I hope it'll worth the time you put in getting whitelisted, downloading the mod, finding a weapon and ammo just to be banned a bit after starting to play lol.
It's not Sarge AI, it's something similar, I guess. There are NPC patrols that are consistent in the world rather than spawn around the general location of the player.
The human NPCs (hazmat "cleaner" teams) have a background story and are imo a natural occurence in a zombie apocalypse (a ruthless faction interested finding a cure at ANY cost) and they are there to make the progression slightly more difficult and keep you on your toes.
Well I'm not sure I understand what you want. If you want what I think you want, then I suggest www.apocalypse-rp.com, look through the features, but look through the rules as well, it might not be your cup of tea.