Why do people have to pay for auto insurance?

I have a 2002 Ford Explorer Eddie Bauer 4.6L. I don't have the full coverage but i still have to pay about two hundred dollars for the insurance? What is the point of that if the insurance doesn't even do anything? At one point a car hit me in the intersection and it totaled and they didn't even help me get it out of the impound? Why do people have to for pay this exactly? I'm sixteen i don't know much about this stuff and my mother isn't always home so i cant ask her.