They also amount to an army of wage busters against the poorest working Americans who aren't union.
No doubt that's true. "Scab" immigrants (legal and illegal) have always provided that counterbalance to organized labor costs and government taxes and regulation. All the way up and down the line we've all taken shortcuts. Who has not worked once when very young under the table? Why file with the IRS, I probably wouldn't owe taxes anyway. Then there's the small busineses. Who can afford minimum wage? Who can afford FICA? Who can afford to check to see if this ratty social security card is valid? Health insurance? Be serious. And then the mega corporations... the smart ones don't hire illegals 'cuz you can go to jail for that. But they do hire those small buisness who hire illegals. No questions asked. What right do they have to check someone else's business? Why should they pay for that? They are trying to cut costs by outsourcing.
So like I said, all the way up an down the line throughout history we've cut corners "to get the job done" which is one reason we are so prosperous. But it is a deal with the devil, is it not?