"Using land the most profitably" (ie. extracting the most tribute) will become de facto ownership for the controlling entity through tribute, while everyone else will be tenants of the few controllers.
I think 'selling' here means "giving the other guy the privilege of having to pay lots of taxes instead of you".
Ownership should be restricted to the community of inhabitants of the land. The processes around controlling the land would be voted on democratically, and a federation of community ownerships with local representation would deal with extra-community processes around broader land decision making.