It's funny, my first job out of college was machine learning for a company processing medical bills to detect fraud on the part of hospitals. It was a very eye-opening process for me as to how American health care is perhaps the worst designed system conceivable by man -- as in, it's genuinely difficult to imagine how the various regulations, incentives etc could be made worse from any perspective (left or right) or measure (human care, cost, equality, whatever). Medical diagnoses are systematized in a rigorous manner through a series of codes (ICD9s, CPTs, DRGs etc), but there is no real set or expected pricing for each code apart from Medicare and these strange agreements between particular insurance providers and particular hospitals (i.e. what defines "in-network" or "out-of-network", where pricing is more or less random). Bills also have an explicit location type (Inpatient, Outpatient, Emergency room, Ambulance etc) and Urgent/Emergency Room care is significantly and consistently the most expensive to the insurer (most American insurance is, after all, high deductible emergency insurance) and thus one of the major vectors of fraud was passing bills off as such. One of the real aspects of madness in the whole system is the pricing disconnect and lack of transparency between all participants: hospitals ask an agreed upon price to insurers who pay it with few questions asked, as hospital pricing drifts up insurers raise premium prices, employers keep paying premiums, and individuals either pay something contractually determined by their insurance company or an essentially random price if uninsured.

TLDR; it isn't at all surprising to me that yet another vulture on American health care expenditure has discovered how profitable emergency rooms can be and that we see such a mad proliferation of urgent care facilities on every corner.