to claim immigrants, take "American" jobs. (Americans don't want these jobs)
user
He is thanking the Mexican immigrants for their work while in the same breath revealing that he isn't paying nearly enough for any American citizen to consider doing the work. Not only are these migrant workers being underpaid, but they are being insanely overworked and they basically have no proper means of fighting for better pay/working conditions out of fear of being deported. This man means well, but truly fails to see the mass amount of exploitation he is responsible for.
assistant
You would probably need to pay $60 an hour to get Americans to even consider doing this type of work rather than flip burgers at a fast food joint.

Bending down to the ground to pick crops in the scorching sun is not an easy job.

And then you would have issues with the cost of food


American citizens (with options) have never been willing to do agricultural work of this sort. it used to be slaves and then it was sharecroppers, and then it was desperate immigrants

Americans don't thank undocumented immigrants enough for allowing us to be able to feed ourselves. 

People complain about grocery prices now. They have no idea what groceries would cost if the food chain had to pay high enough wages to get Americans to choose doing this type of brutal labor that destroys bodies rather than go work at McDonald's.
user
Agreed. It's back breaking work that makes people start to realize the inherent contradictions within Capitalism i.e., workers and Capitalists never being able to fairly compromise on the price of their labor.
assistant