In an emergency situation, hospitals are legally obligated to provide the minimum care necessary to stabilize the patient, but not necessarily cure them or restore their health to anything approaching whole. They are not required, and in the case of for-profit hospitals will never, provide the same level of care that an insured (or wealthy) person would get.
For example, if an uninsured person is brought to the emergency room with a condition that has cancer as it's root cause, the hospital will treat the immediate symptoms, but is not obligated to provide surgery, radiation or chemo-therapy. That person may receive medication to dull their pain, but in the end, will be sent home to die.
This is exacerbated by the fact that, without health insurance, many people have no access to doctors before the emergency room is needed; thus, many conditions that might have been headed-off in a more treatable state (infection, diabetes, kidney disease, etc) are instead only addressed when treatments are more extreme and more expensive and when recovery is much less likely, if not impossible.
(BTW - In many places, there are no "county" hospitals anymore. In fact, there are fewer and fewer non-profit hospitals, overall. For-profit companies, like the one run by former-Senator Bill Frist's family, operate hospitals in much of the country and are often the only option to patients. This profit motive on the part of hospitals adds additional costs to the patients)
Additionally, a doctor who worked as an administrator for an insurance company testified before a congressional committee that her job was to maximize profits by denying treatment to insureds as much as possible, and she knew for fact that PEOPLE DIED because treatments were withheld entirely or delayed until they were beyond help. The insurance industry has recently been lobbying their friends in congress to add provisions to any insurance reform legislation that would allow them to keep as much as 35% of every premium dollar as profit (for comparison, gambling casinos are only allowed to skim 20 - 25% of every dollar gambled). BTW - the administrative costs of Medicare are 3%; 97% of every premium dollar goes to treatment.