I respectfully disagree that this thread is 100% about legality. Many, many posters have addressed the character and actions of the people involved. It is on topic. I agree that there is a legal aspect to it but morality is always an issue. It's what you do about it that is the question. I'm with you that we shouldn't be prosecuting people for moral failings, but they are certainly relevant to society.
The owner who erected the fence broke no laws that I'm aware of. If he has then it's a different story. The only immorality I've seen in this thread comes from those who "playfully" say that if they lived there they'd take matters into their own hands. They are the sole perps of immorality and illegality here.