Do you think it's OK for corporations to take advantage of illegal immigrants? I don't understand the point you're trying to make here, Franklin. You say from the point of view of the supervisor that a worker who will work harder for less money is a better worker, but the supervisor doesn't give a shit how much the workers are paid, as the supervisor is a paid employee. It's the business owner who benefits from the cheap labor. The business owner also benefits by not having to pay taxes for the undocumented workers, which doesn't help this country either.
Now it seems like you're arguing that immigrants make better workers because they believe in the "American Dream". I don't know what this actually has to do with illegal immigrants. They are looking for a better life, obviously, but by not being in the country legally they're denied real success. It's their children who end up living the dream, but they're not immigrants if they were born here.