Other organisations are similar tasked, but they don't go around randomly accusing people of criminal behaviour, with zero evidence.
The police don't assume every household without a Firearm Certificate, has an illegal gun.
The NRA don't assume every household without a fishing licence, is fishing illegally.
The DVLA don't assume everyone who doesn't hold a Driving Licence, is driving illegally.
BBC/TVL, however, assume anyone who doesn't have a TV Licence, is watching TV illegally.
As for you last question, there's a third category of people, which is those who have neither been prosecuted and convicted, nor made a claim of non-live use.