If Americans won't keep the slave quota filled, then they will go find them somewhere else. Plus, immigrants are not inherently hostile to American oligarchs like we 'locals' are. We expect things like fair pay and fair representation and protections against retaliations just because we won't become real slaves to these wannabe feudal lords. The immigrants would not be aware of just how greedy and sub-human our corporate-controlled society has become.
I saw a post on Reddit where someone was laughing about the fact that some of us seem to think that greed was invented by Americans. No, it was not. Nor is greed anything new in human society.
But, I would wager that no society in history has ever taken greed to the levels that we see today. Not and gotten away with it so cleanly. 
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