Although I think the article in the OP illustrates bad manners at worst there are most certainly abuses in the profession. As in any other profession, BTW. As for speedcameras and the like. A lot of it is decided on an entirely different level than the cop doing the actual work themselves.
Like where I work: the industrial zoning now only has two exits because of roadworks and there's plenty of big stores here. Instead of regulating trafic at the exit intersections Cops are positioned at likely 'escape points' to fine anyone trying to get in or out through some company's parking lot instead of the road. It's pretty disgusting, but I don't think the cops doing that work went ahead and decided it'd be more fun to do that instead of helping trafic. It's decided much higher up by city officials who lack the necessary feeling and knowledge to see that this is ruining the image of their own industrial zoning and think of it as easy money. I bet it's like that in a lot of places.
2008 audi A3 1.9tdi
(former 1991 520i LPG)