I really liked digby's post about how it is in the self-interest of even rich people to help foot the bill for creating a stable and comfortable society. I'd really be taking it in the shorts if I started out with enough wealth to think health insurance wasn't necessary.
I've been thinking a lot about the value of spreading costs around, given how much I've had to rely on insurance this year, and how much better an investment health insurance turned out to be for me than just keeping/saving/investing my money. I was an unusually risk-averse 21-year-old. I'd be absolutely buried under debt now if I didn't buy health and disability insurance years ago. You really don't want the kind of return on your investment in health and disability insurance that I got, but I knew that beforehand.
I'm an exception (one in thirty million is the incidence of the condition I ended up with), but I'm sure glad that I've got 29,999,999 others to help pay for a freak health incident. Looking back, it's nice to know that my insurance premiums during my years of perfectly good health were helping defray these kinds of costs for others.