This from Kurt Eichenwald a couple weeks back at Vanity Fair magazine:
The first thing to understand is that when people don’t have insurance, it hurts other people with insurance. In fact, the uninsured affect the finances, quality of care, and availability of medical assistance to every person in a community, regardless of their insurance status.
This is the fundamental issue that too many people do not understand. There seems to be this belief among some that those who are uninsured simply go off and die somewhere, thus having no impact on the medical-care-delivery system in the United States. But the opposite is true—the uninsured have some of the most dramatic effects of any group on our nation’s health-care system.
Here’s why: they seek out care, but usually when their once easily treated conditions have blossomed into a serious illness. Because private doctors do not take them, and because free clinics are not readily available, the uninsured seek their care in emergency rooms.
The rest of the article is full of great analysis and discussion of medical economics and is well worth a read. But I wanted to highlight this fact specifically.
Also ran across another blog post, this one relating a personal experience with cancer, that deals with this issue:
Obamacare requires insurance companies for the first time to cover everyone, regardless of any preexisting conditions. There's no more disqualifying condition than cancer; without Obamacare, I would now almost certainly be uninsurable if someday in the future I try to get insurance on the individual market. And we know what happens to people without health insurance in the United States: they die.