The idea that sick people who have no insurance can just routinely use emergency rooms for their care is false. The provisions of EMTALA only require hospitals to treat such persons if they are at severe risk of death or in active labor, and even then they need only be treated till their immediate condition is stabilized. While there are emergency rooms that treat more, it's completely legal for them to turn patients away if they don't meet these conditions, and they often do. Many people in such circumstances suffer from serious chronic conditions for long periods of time that would otherwise be treatable, but end up only being accepted for emergency room care when it's too late to successfully treat their conditions. A rather large number if American citizens lose their lives every year because of these circumstances. So the notion that we can comfort ourselves with the argument that there are only problems of economic inefficiency bedeviling our system when it comes to the uninsured is a conceit. It's a moral issue, and I think a serious one.
But many uninsured do routinely stop at the ER for lack of an alternative. The best solution is to connect those people with a primary care physician. That overcomes economic inefficiency and works to identify conditions that could be effectively treated at an earlier point.