“Ex-slaves, in large part, shared a different economic vision. They were "always on the move," searching for family, denying their labor to "dishonest or oppressive employers," and asserting their independence through their mobility. Rather than staying in place, working as much as possible for a high a wage as possible, and thus possibly accumulating a greater array of material good, a large number of freedpeople sought not to maximize income but to minimize the amount of "time spent at work on other people's behalf.”