Say everybody has ten acres of land, because we've taken all the land and divided it out among the world's population. Let's leave aside, for a moment, that's pretty much impossible, since everybody will want beachfront property in Hawaii, say, and not a patch of desert in BFE.

Now say I have fifteen children, and you have one. In the next reallocation, do we really divide out the land such that my family ends up with fifteen times the land your family has? Think about the incentives that kind of scheme creates.

Furthermore, there's a tragedy of the commons problem. If we all own the land, or it gets re-divided every generation, I have no reason to improve it. I'll get rich turning my land into a toxic wasted dump, because I don't have any interest in maintaining its value.

In the end, that's why we have property ownership. People don't take care of things they don't own.