If people aren't getting sick, they have no revenue stream. Those non-profits you mentioned obviously aren't as capable of lobbying congress to influence industry regulation / bureaucracy as for-profit organizations are.

Nonprofits constantly lobby congress for a huge range of reasons, but they also get results with a surprising amount of federal money going directly to such organizations independent of Medicare, Medicaid, etc.

> If people aren't getting sick

People also get sick outside the US.

People still get vaccinated in the US for diseases with effectively zero new US cases because they haven’t been eradicated worldwide and would come back as soon as we stop vaccinating people.