I've known some of those guys who hire illegal aliens as part of their business plan. Most of them are not bad guys. The ones in manufacturing are getting mercilessly squeezed by Chinese competition -- which often directly copies their products. In turn, their customers -- retailers -- are getting the snot squeezed out of them by Wal-Mart. The ones that I know aren't guys buying beach front condos in Hawaii with the salary savings. They're fight for their businesses.
That cheap labor is now a necessity for their survival.
That said, manufacturing can be done with American labor. Alden shoes, which are made entirely in the U.S., uses only "legal Americans." They make an excellent shoe, but their market is quite limited as $350 to $600 or so is at the upper range or out of reach of a lot of people.
I know of several people who deal drugs to feed their families and have that extra cash so deperately needed to take care of their children and just maintain a status quo, much less buy a beach front condo themselves.
Drug dealing is illegal, so is hiring undocumented workers. Both need to be put out of business otherwise our society breaks down.
Once we get the idea it's ok to break a law with impunity, any law, then we've lost our right to a lawful and ordered society. It's the job of the police to arrest people that have broken the law, it's the jury's job to figure out if there is a problem that needs to be dealt with. We already have a structure in place to deal with the grey areas.
If a company needs to break the law to stay in business, it should NOT be in business. And you can bet it's producing a profit if it's staying in business! How different is that from a business owner who robs the local liquor store to pay his bills and then pockets what's left?
How can we in good concience give amnesty to 11 million criminals so they can keep working when we have almost as many good citizens who could step in and do those jobs? Would you ever even consider giving amnesty to the inmates of your local state prison simply so that they are no longer a burden on society? Why is it ok to give amnesty to someone who premdiated their crime then executed it deliberately when they came here and repeat the crime on a daily basis, yet not to the criminal who was in the wrong place at the wrong time and tried to profit from the situation (as many criminals in state prision end up being)?