It's interesting to see what happens when videogames behave more like real life. For instance, in Oblivion (and Fallout 3), you can't just take things unless you're in the middle of nowhere. If someone sees you, they cry out "stop, thief!". Equally, attacking people who didn't attack you first in civilised areas will draw the guard or vigilantes down on your head, and most of the stuff you find lying around is worthless trash that isn't worth the effort to haul away and sell.

I remember how jarring it was when I first tried to take something in Oblivion, only for a bystander to call for the guard. And then I realised that this is how NPCs should react to casual theft.