Immigration in the US has always been more complicated than "no papers? gotta go." Moving north to do some seasonal work then moving back south is a very old thing, and was enshrined into law by the "Bracero program" in the post ww2 era. In the 60s, however, it was ended abruptly, giving migratory workers no choice but to stay illegally. ... and business owners no choice but to keep hiring them.
The idea that illegal immigrants need to be deported (and not have a path to legal residency) comes from a view that those jobs should go to American citizens (which will bring economic pain that is intolerable) or from a view that browns don't belong in the USA.
The idea that illegal immigrants need to be deported (and not have a path to legal residency) comes from a view that those jobs should go to American citizens (which will bring economic pain that is intolerable) or from a view that browns don't belong in the USA.