Since the encryption does not prevent copying, but the keys are distributed in a controlled way -- players with certain keys are only available in specific "trade-zones", it seems that their goal was to prevent piracy of products *between* trade-zones, e.g. the pirating of Hollywood movies by people in southeast Asia, rather than within them. (It's well known that a lot of U.S. intellectual property is available from street vendors there at some very deep discounts:-).)
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Since the encryption does not prevent copying, but the keys are distributed in a controlled way -- players with certain keys are only available in specific "trade-zones", it seems that their goal was to prevent piracy of products *between* trade-zones, e.g. the pirating of Hollywood movies by people in southeast Asia, rather than within them. (It's well known that a lot of U.S. intellectual property is available from street vendors there at some very deep discounts :-).)