It doesn't happen often that people are sued for their own unpaid medical bills. Usually the provider sells your debt to a collection agency for whatever they can get.
e: to clarify, the reason it's uncommon is because most people who don't pay are failing to do so because they can't so there's no point in suing them. obviously when someone has a lot of money and isn't paying there's incentive to go after them, which may be what's happening here.
e2: to clarify further, in states with expanded Medicaid (like Kentucky) all the poor people have Medicaid, so most of their medical bills are paid, certainly their ER bills. So if you have unpaid ER bills to begin with in an expanded Medicaid state, it is assumed you make enough money that you don't qualify for Medicaid (read: you have considerable wages to garnish), so you're more likely to get sued. In states that don't have expanded Medicaid, poor people run up huge medical bills because they have no coverage and obviously no one bothers suing the destitute. Sorry if that was confusing.