Can you propose a different model for property ownership which doesn’t require the individual to invest more resources in physical security?
On another tack, there are plenty of homeless people in the UK. Can you imagine what would happen to them if they broke into expensive uninhabited properties in London? There would be violence.
I have no idea of alternatives, I was just pointing out the origin of a lot of current land ownership.
You could also argue that as the ownership is codified in laws and the state monopoly on violence keeps the oppressed in check, that threat of violence continues.
This is not about land ownership. Alone. You are talking about exclusive political and economic systems. In an exclusive system it's not just the ownership of land that is broken - you will find all economic activity is rigged against some segment of the society. Most well to do states are have inclusive political and and economic systems. In these societies land ownership is based on land registration and enforceable contract law - not entitlement of birth and violence.
I warmly recommend Daron Acemoglu's "Why nations fail" as it explains this topic far better than I ever could in a few sentences.