Economics teaches that people reveal their preferences through their actions. If people act as though they are indifferent between being uninsured and being on Medicaid, we may infer they are equally well off in both states of the world from their own point of view. If someone drops a $20 bill on the floor in Parkland’s emergency room, how long do you think it would stay there? Probably not very long. If someone drops a Medicaid enrollment form on the floor, how long do you think it would stay there? Probably until the next janitor comes along with a broom. Health economists tend to think Medicaid insurance is really valuable – worth a lot more, say, than $20. Many patients, through their actions, communicate that they disagree.

This is from John Goodman, “Is Medicaid Real Insurance?” Worth reading.