Had the same experience during my visit. Some older Russian doctor who chatted with me for 15 minutes, telling me that America was ok, that green card medical visit were pretty much all she was doing now, 3 half-day a week and that was plenty for her to make good money. She pocketed the $600 and gave me the sealed envelop.

I have no problem with not passing any cost to the American taxpayers (and even that could be debatable, yes I'm an immigrant but I've never been unemployed and I believe I create wealth so it's a full net win for the country), but the system is really hostile and dysfunctional.