"Though much has been made of the system of peonage that kept sharecroppers in perpetual debt, tying workers to the same plantation year after year, there is significant evidence that Georgia croppers moved rather fluidly from place to place and from one form of labor to another. Certainly the reality of life as a sharecropper was a factor in the out-migration of rural Georgians in the 1910s and after. The sociologist Arthur F. Raper found in his study of Macon and Greene counties that of those Georgians fleeing the rural part of the state in the 1920s, the greatest numbers came from the ranks of sharecroppers."

Frankly, it sounds like a system of unjustly exploiting ignorant poor people that was roughly on par with the one described in Chicago in "The Jungle" at the same time. But that's pretty much what I thought before I read your link, too.

Maybe you could describe what sense you think it fails to 'meet the standard of "completely voluntary"' in?