Walking in NYC is a lot like driving is in other places. You become really irritated when the people in front of you are moving too slow. You try to pass people and duck in, while keeping an eye on oncoming traffic (people). Being cut-off by someone is the most annoying thing in the World. People who try to cut across the stream of traffic (crowds) take their lives in their hands. People in front of you who seem to not know where they are going is enough to drive you insane. In some ways walking in NYC is more stressful than driving because you can't rely on other walkers to follow basic rules of the road (or sidewalk).