It's also a slap to people like Chad who came here from other countries .
In the interest of full disclosure, I was born a US citizen by parentage, so I have never had citizenship issues in the US.
And to address the "they do work" point, when I talk of self sufficiency, part of my definition is that they are doing it legally. Working illegally, receiving unpaid medical care, bogging down public aid systems (welfare, food stamps, section 8 housing) without being legally here... these things are NOT part of self sufficiency.
Here in New England we don't get many Mexicans, legally or illegally. Maybe they don't like the winter, or there are closer places to go. What we do get are huge amounts of illegals from Puerto Rico, Dominican Republic, Haiti, places in that region. We also don't have the vast amount of nonmonitored field style work that other parts of the country have so you can't just pick up a truckload of illegals to do a day's work. Unfortunately, what we do have, at least in MA, is probably far worse. We have a ridiculously forgiving and uncontrolled welfare and housing assistance system. You don't have to be here legally, you don't have to work, you don't have to even comply with the program requirements. I used to see it firsthand... you'd have 3 families in one state paid 3 bedroom apartment, all receiving welfare and food stamps, half the adult residents with nonreported jobs, no intention of becoming legal residents or of contributing to society. When some official finally catches wind of it and sends a person to investigate, the families just pack up and head right back to their country of origin, having lived a far better life in MA off the state for several years without contributing a thing.
My mother had friends who worked in one such offices and the stories they would tell boggled the mind. One in particular sticks out. We had one woman who had been on benefits for years, didn't speak a word of English and seemed particularly slow. It would take them months and months to get any single piece of documentation or response from her and when they did it was never complete. She would say to a translator in broken Spanish that she didn't understand. Well, one day after about 8 months of trying to get one piece of paper from her, one of the new social workers says, "what the hell, this woman must be a total idiot" out of frustration. Inappropriate, yes, but the woman responded by turning around with a "how dare you" and a 30 second articulate tirade about how the worker had no right to insult her. In English. That's only one individual but stories like that were far more common than one would want to believe.
Now, I'm not against assistance programs. Sometimes people need them. What I am against, strongly and always will be, is assistance programs being available to people who are not AT LEAST legally documented residents. Can't speak for the rest of the country, but here in MA, if you got rid of just that you would have revamped and dramatically improved the entire state assistance program.
Unfortunately, in MA, that is just the tiniest of drops in the bucket in terms of our state gov't, and no politician will ever dare try to do this.