In fact law enforcement has arrested people for illegally using Ham radios without licenses. Pirate radio and the like.
There was a time when the FCC had enforcement people. Now that is focused on the commercial side, where the money is.
The Ham bands are largely self-policed. And I might add that has worked pretty well. An inexperienced operator sticks out like a sore thumb.
I first sat before a FCC examiner in the Federal Building on Commerce Street in Downtown Dallas in 1976. Things were a bit different than they are now. My extra class and my commercial license came later.
Until recent years so many hams were either trained in or served in the military that you were hard pressed to find a Liberal amoung their ranks. I ran a Navy MARS station out of my home and from my car for 19+ years. Many of my friends when I lived in NM worked in the Labs or Military bases. I miss that crowd, good techies.