lol sometimes npc's can help to significantly move a plot along. They can also make for great scenery. At some point, aren't we going to hit a reality that has people in it? Those townsfolk are npc's. If we kill one of them, they might not notice for a while. If we do it in public, we could potentially have a riot on our hands. If we make friends with them, we might gain knowledge of an artifact or an anomaly. Maybe a place to stay like an inn or tavern. Maybe a thief takes something of ours and we hunt him down. You can kill and npc thief. So on etc.