On the other hand their productivity in a well organized sorting facility might go up, such that you're paying them a fair and legal hourly wage but the price p

On the other hand their productivity in a well organized sorting facility might go up, such that you're paying them a fair and legal hourly wage but the price per sorted item remains similar. Maybe. There are other complications though. The willingness of the public to employ such people, and the willingness of such people to be employed.