Fundamental and covenantal

The violation of the laws of sheviit carries with it in particular the consequences of overturning the covenant. 

That's why the laws of sheviit are introduced with the expression 'These are the laws God gave to Moshe at the mountain – bahar." The laws of sheviit apply with the same force as all those covenantal events that transpired at Mount Sinai, which events applied to the people and to God in the wilderness in the immediate setting of the mountain. The laws of sheviit are not simply details about how to do this and that, they go directly to the existence of the covenant, if not in the first place (in the wilderness) then certainly as they apply to the future situation when the Children of Israel will have taken possession of the Land of Israel. 

The laws of sheviit are fundamental and covenantal. The difference between the laws of sheviit and the initial covenantal rites at the mountain is that the laws of sheviit apply only to when the people take possession of the land while the initial covenantal rites apply even outside the land. 

Other laws also take effect only after the people take possession of the land but those laws are not covenantal. The discussion of their violation does not carry with it a disquisition about how, as a result of said violation, the covenant would be overturned and the people expelled from the land and relegated to the ignominy of exile.