What are the lines for, exactly?

There is a particular road, a fairly main one, that has been recently decorated with its very own street lines. These gave me hope that there would soon be more organization on said road and perhaps more predictability in the driving patterns there. However, instead I followed a car for some distance yesterday morning up that hill and instead of passing it, I merely followed and laughed. This particular driver seemed to think that instead of driving between the lines, one was supposed to drive so that the line went directly down the middle of one's car, effectively taking his half "out of the middle" of the road. Other drivers completely disregard the lines as if they don't exist. I guess I always thought that people naturally drive within boundaries, but it must be something I learned through experience, or part of the way my culture thinks. Order is good, we say. God is a God of order. We like order. But these people don't always think that way.