In all honesty, while there are plenty of good reasons to dislike drones, I think this is a terrible one. You're worried that drones would allow them perfect enforcement of laws? How is this a bad thing exactly?
Worst case I can think of is that they are enforcing bad laws in which case right now they might slip by because "no one ACTUALLY pays that fee!" except that a widely ignored but still on the books law is unfair to anyone who actually does follow it, or leaves it as an opening to target a person who hasn't done anything else wrong.