The key difference is in the amount of liberties and the wages: prisoners in the US are forced to live in tiny cells for years and most importantly, are paid $0

The key difference is in the amount of liberties and the wages: prisoners in the US are forced to live in tiny cells for years and most importantly, are paid $0.25-1.00 per hour - a symbolic pay just for the prisons to be able to say they're paying prisoners and not using them as free labor. Worse, the prisons actually get paid (a lot more) for providing these people to companies AND they get paid by the government to keep the prison system running.