Kimberly, the plexiglass sounds like a perfect solution.

I'm glad my fence is a privacy fence. Kids walk by all the time and they can't see my dogs but my dogs can hear and smell them so they bark at the kids. I also have several beware of the dog signs in case anyone wants to get stupid and climb over which no one has ever done.
It's just amazing what people do anymore. I'm so glad my GSD has a deep loud bark and now my mountain dog is barking right along with the Shepherd when he hears or sees someone. We live in a Cul-de-sac and occasionally get people selling things door-to-door and Jehovah's Witness folks. NO ONE comes to my door because my dogs will see these people across the street and start barking. The UPS drivers won't even come to the door. They leave our packages on our driveway.
I like the plexiglass idea. I also like the punching in the face idea but that would be a law suit. I like the idea of letting the dog take care of the moron but again, law suit. One of these days that guy is going to kick at a dog that can get out of the fence. He will be singing falsetto after that!!