If you transport drugs in your car or cook them in your house, the Gummint will confiscate your wheels or your digs. Suppose they confiscated and auctioned off businesses that make a practice of hiring illegal immigrants?
I suspect legal scholars would promptly discover that civil confiscation violates due process, the number of businesses hiring illegals would decline rapidly, and the clandestine economy would grow . . . Whether border-crossing would decline, ¿Quién sabe?
Like I say, just a thought experiment, like Schrödinger’s cat.