Speed trap to me is when the intent of enforcement is financially based for a city rather than to solve a problem. An area that has few accidents should not have heavy enforcement. Sometimes cities lower speed limits in areas where no problems existed and then place police patrols along.
This situation occurred in Scottsdale, AZ along the 101 freeway. They placed many speed cameras that tripped at 11mph over. After legal challenges that there was never a speed related issue warranting the cameras and that the tickets did not lower accidents they were removed. It was clear that the purpose of the cameras was to raise money and not solve a traffic problem.
That said, I do not know the situation in Waldo but 'speed traps' do exist and they're wrong.