I may be wrong, but I think you can call out a hobbyist on your local board for either meretricious or merit-full behavior as clients are able to do so about providers; though it is very rare, and probably for good reason too.  Of course no RL names can be used.

There are various "black lists" where providers can dish out dirt on clients for various reason, and RL names are used there

... the Providers Only board, once you're eligible to join. Maybe a provider could tell us if there's ever been a "review" of a hobbyist there.