Look, some portion of unisurds' ER bills, that are negotiated down to actual below cost to the ER for the treatment, are passed on to other consumers via inflated bills to insurance companies. That's not a debatable point. However, it's also true the feds do pay some to the states for uninsured visits, as you said. It's also true, however, that the feds decreased this amount with the ACA, reasoning there are less uninsurds. That's a problem for hospitals in my state, where the governor chose not to expand Medicaid.
NEVERTHELESS, it's also not debatable that insurance companies also negotiate the price downwards.
I'm sorry its personal.
But the entire sorry subthread does illustrate a pre-ACA problem that the ACA did nothing about. There's no way to find out what something's gonna cost before you buy it. That's a crazy market there. Unless you fix that, you aren't gonna fix it at all.