Actually, one could read the Constitution quite literally as simply saying that just compensation is necessary when private property is taken for public use. It does not actually forbid taking private property for private use, nor does it even require conpensation in such case. Of course, that's probably because the framers thought that the wrongness of such takings was so blatantly obvious as to not need mention.
Is this not correct?
"The due process clause of the Fourteenth Amendment has been held to require that when a state or local governmental body, or a private body exercising delegated power, takes private property it must provide just compensation and take only for a public purpose. Applicable principles are discussed under the Fifth Amendment."