So true, the useless NPCs decimates my performance massively. However, I feel uneasy when I'm exploring somewhere that contains no NPCs. It makes me feel like I'm in a horror movie and something will pop up on me.
I wish something would! If we can't have a properly populated wasteland then just filling it with frightening monsters and phenomena would be great. The fallout games, especially Fo3, provide a great setting for a good horror survival game.