I've lost a combat armor MK II (I'm low level so that kinda hurts for me) today because a PK entered my encounter while I was burning mutated mole rats for xp.
Next time you're going to hunt scorpions don't forget to get PA and gauss.
About NCR: opposite, NCR is a place where you can get items without even doing anything, you can be even afk 95% of time and just loot innocent people who died from suicidal maniacs, trolls, bombers, crazy bursting guards, idiots, GM abuse or NPC abuse or some other sort of silly death. If you don't want to lose items in NCR, there is really easy solution: come there naked! If you have no items, you can't lose it! Or at least keep armor on you and item(s) in your hands, if you have more than ~50-60 HP, you have low chance to die because of random suicider.
Also those items, accumulating items, crafting them, what for? If you're alone, you won't use anything above jacket and pistol anyway (oh, right, you can hunt molerats in CAmk2), because if you'll handle something alone, it means you don't need high tier items, and if you need high tier items for something, it means you'll die there alone anyway.