The US government has put in place extremely heavy barriers to open a medical care facility
That's not true at all. The federal government wouldn't gave any reason to intervene unless you end up falsely billing a Federal program like Midicare, Medicaid, or VA.The reason for consolidation in ERs is cost -- uf you run an ER, you are obligated to treat anybody who cones in without regard to ability to pay. It's a money pit in many urban areas.
https://www.vox.com/policy-and-politics/2018/7/31/17629526/m...
A lot of their customers will be unable to compare multiple hospitals and "shop around", so to speak. Either because their conditions is life threatening, they're actively dying or they're no longer responsive. The ambulance, in any rational scenario, will drive you to the closest hospital in terms of time-spent-driving
So from a corporate perspective it's perfect; the customer arrives and you're legally obligated to start spending money while they are likely unable to object and then you can bill them for it.