Case C-70/09: Judgment of the Court (Third Chamber) of 15 July 2010 (reference for a preliminary ruling from the Verwaltungsgerichtshof — Austria) — Alexander Hengartner, Rudolf Gasser v Landesregierung Vorarlberg (Agreement between the European Community and its Member States, of the one part, and the Swiss Confederation, of the other, on the free movement of persons — Lease of hunting ground — Regional tax — Concept of economic activity — Principle of equal treatment)