A proposal by Atlanta-based Grady Memorial Hospital to increase medical costs to some uninsured patients has alarmed advocates who say people will avoid care, become sicker, and perhaps even die. Grady officials have stressed that the proposal is still in the discussion phase, but acknowledged it could cut off some people from free care. Some of those people receiving free care have been abusing the system, and others have the finances to pay at least part of their bill, said Grady CEO Michael Young.