I wasn't endorsing any of the options, just stating that they occur.
No one can control what the markets will do. Every person runs a certain amount of risk that there may be a glut of his or her skill set in the local market for whatever reason and has to consider a plan b of action should the worst occur.
I would offer that allowing the illegal labor force to continue and allowing it to even augment is manipulation of the job market occuring as we speak.
Plan B is always a good idea.