My father is an executive at a major hospital and this is only part of it. There is also issues of brands forming monopolies when appearing in communities. Mergers are also incredibly complex. Also lots (but not all hospitals) are nonprofits which complicates it further. ERs are required to treat patients if they come in which means some are making tons of money while some not at all. One person can significantly alter ERs profits[0].
[0] https://www.beckershospitalreview.com/finance/the-12m-patien...