I understand where most of you are coming from, but hear me out:
What is it that gives us such a huge adrenaline rush and thrill when we are in a fighting, shoplifting, or say being chased by an old farmer with a shotgun in real life? It gets our hearts beating because whatever happens, it is FINAL and we must bear the consequences for our actions, whichever way they go. If we could reload after every decision, there would be no thrill, would there?
Most of you are taking the argument of self-restraint, but even knowing that you have the option to reload to before you murdered "X" NPC kind of dulls the finality and thrill, don't you think? Yes, things would be scarier and you may have to play the game much more carefully, but I really think it would make for a more enthralling and more fun experience on the whole, even if you can't repeatedly go on a killing spree, which you must admit does get a tad boring after the 10th time.