No, I did not say that, but others on this thread have. I have said that, if these people do the job better, no one in his right mind would not want to hire them. And, if you are doing business with a contractor who is not a good businessman, be careful.
As for their wages, I have had Mexicans work for me (legally), and paid them exactly as I paid anyone else: according to merit.
I hate to bust everyone's bubble here, but a $10 hour went a lot further for my customer with a Mexican laborer than with a white one, about 3 times out of 5.