Agreed, the primary goal of an insurance system is to POOL risk.
I don't agree entirely here, and now we are coming up on precisely what's wrong with what insurance has become in practice, rather than what it should be. As Ikari said earlier, the goal of insurance is to pool risk. In an ideal insurance system, participation would be completely voluntary (this is important) and everyone who chooses to participate would be paying the same rate. Under such circumstances, people still have the economic incentive to live healthier lives, or engage in less risky driving behavior, because curbing such behavior would lower everyone's premiums no matter who they are.
Once the insurance starts pricing in risk into premiums, it ceases to function the way insurance is meant to function, and instead you effectively have a market-based, pay-go system in all but name only.
Now, this is purely my opinion about how an ideal insurance system should actually work. My opinions on how the ideal healthcare system should work are an entirely different matter.