Earlier quoted context omitted.
Because the system is designed to allow these people in a gray zone, so they do not have access to the same rights as citizens and therefore can be exploited. The problem is not illegal immigration. It's just a political football. Our economy would fily collapse without this cheap labor to exploit.
It would not collapase. But it would shift some purchaing power from the middle class to the working class if all of them would leave, as working class salaries would go up even faster than the inflatino it would cause.
please tell me that's not a typo /g