The real problem is that a huge part of our national economy has fallen in love with, and absolutely depends on, the wage busting effects of illegal immigration. Entire industries (construction and food) have priced in the low cost of labor due to illegal immigration. Obviously some of that is pocketed by the company, but a lot of it also filters out to the consumer in lower prices. And to make things worse, the same people who claim to want to stop illegal immigration (everyone) are its biggest promoters/supporters.
If you are a home owner and have any major work performed on your home - and it doesn't matter if you hire the Mexicans directly or even if you go to a contractor that is legit/licensed, the chances are that illegal immigrants are going to do the work. Now, if you are serious about wanting to prevent illegal immigration expect to pay between 30-50% more for the work.
There is more than enough empirical research to support the position that it is a net negative for black people but unfortunately we Americans always cry about shyt just to go along, knowing damn well we have no intention of paying the true cost of our choices.