I can see why permits might be required of pros who are bringing lights, generators, assistants and all the rest, but it seems a little over the top for one guy and a family getting a portrait or some such.

In the case of the OP, I read about this in some other forum, and the ordinance deems a photographer a "professional" if he is using a tripod, or a camera with interchangeable lenses, among other things.
So, if you're going to make a photo in one of Overland Park's city parks with anything other than a P&S or a Holga, congratulations, you are a pro.