Tell that to the insurance companies who always knew that they could indeed do this (and have done it including a couple people I know), while all the while knowing that the government WILL NEVER come in and punish them, and it is also highly unlikely that they will be sued by the customer. It's hard to sue a corporation that has a phalanx of attorneys facing you, and it's also unlikely that an insurance company will be sued because they "skipped town" on paying for $23,000 of covered expenses, because the customer also know that they will just appeal unfavorable decisions until it reaches a court that the company "likes" and the plaintiff has probably spent $100K or $200K trying to get $23,000 (and an uncertain amount of future costs that would be covered)...and they STILL don't get their insurance back.
Then, they would be absolutely uninsurable in some states that don't have "emergency" insurance pools, and in the states that do, the premiums are usually insanely high.
At least, this was true before ACA, which related to the timing/history I was talking about. I am certain that Obamacare is saving FAR many more lives, than the number of lives that are being destroyed by it. Because no health care system will ever be PERFECT, not even the single-payer that I yearn for (which Medicare is, at best, only a hybrid of), there will always be winners and losers.