There are no economic systems that innately correct just as there are no mathematical axioms that are more than an agreed set of rules. Everyone used to think for example parallel lines never met until Gauss started to question it. All economic systems work to some degree, communism worked, socialism still works, fascism works, dictatorships work, but all have various flaws that can make them unstable or inefficient. So which is the "right" system and who gets to decide what is "right"? The idea that private property and one's possessions are one's own is not a principle it is a made up rule of a game one decides to play.
So your real question is, why doesn't everyone prefer the system I prefer? Ayn Rand of course asked the same question and tried to imagine a society that ran that way. Perhaps that leads to the next question, if this is so self evident and correct why has no society in the history of man ever been run completely that way? You would think if it was so obviously true then somewhere everyone would have preferred it.
In fact the principles you are saying are simply radical to all known civilisations so far. There have been many cases where people have accumulated wealth through trade in peace, and then when there is enough of an imbalance then the poor take some of it back by voting or force. The thing is the poor know that they will do better under some socialism and see know reason to pick the rules of a game that guarantees they lose. Unrestrained capitalism doesn't work for the poor, it never has in the history of man and it never will.
The system that does work is a mix of socialism and capitalism. Knowing as we do that that works the question then is why do you prefer a logical system that doesn't work for everyone?
You give the example of someone being robbed here is a counterexample. A few people have accumulated all the money and food and the rest of the people have none. Why should they starve because of a so called moral property right, and what is so moral about them all starving?
There is no Robin Hood principle involved, it is setting up an arbitary set of economic rules that favor one group, namely the smartest, the strongest and the sneakiest. The rest of the population has no obligation to prefer that system.
Zoning officials are a good example, when there is no control over zonings you end up with slums and a complete disaster. How could this be possible if the principles you are saying are logically impossible to be wrong? Unbridled capitalism destroyed Argentina's economy just as it is destroying the US economy.
You can't convince people because you are wrong. Private property is only an abstraction and doesn't even exist. Who owns the air that runs through your property, the animals, the rain and who own the evaporated water? It is physically impossible to describe all things in terms of ownership because it is impossible to define everything in terms of objects.