It bears repeated emphasis that we do not have under consideration the property or privacy rights of an individual homeowner or the proprietor of a modest retail establishment. A handful of additional orderly persons soliciting signatures and distributing handbills in connection therewith, under reasonable regulations adopted by defendant to assure that these activities do not interfere with normal business operations ... would not markedly dilute defendant's property rights.
Pruneyard at 78, 100 S.Ct. at 2039 (citations omitted).
Our cases make clear that the impetus for the forbidden discrimination need not originate with the State if it is state action that enforces privately originated discrimination. Shelley v. Kraemer, supra.