You might want to check the immigration status of the guy who built their doctor's office, the girl who works behind the counter their, the couple that cleans it, and the repair man who keeps it working.
Then notice that the doc himself is an immigrant who got his Visa because we need MDs. Of course, his lawn, and the crew that built his house... well...
So, I suppose their health-care provider, like yours, might be mostly immigrants.