in the old fashioned world of physical domain squatting - i.e. land speculation - ramping up land taxes (as some percentage of the current valuation of the land

in the old fashioned world of physical domain squatting - i.e. land speculation - ramping up land taxes (as some percentage of the current valuation of the land) is one way to discourage this kind of thing. perhaps not the best way, but certainly a way to go about it.