Why do we owe illegal immigrants anything?

I here a lot about it being impossible to remove 12 million illegal immigrants from the country and therefore we need to make them "legal" overnight and provide a path to earned citizenship. Excuse me but this country has never shied away from doing the impossible. Employers that employ illegal aliens must be severely punished and when the jobs dry up for the illegals then those illegals will go home. Every foreign citizen that wants to work in America or become an American citizen must do so according to the laws of this country. Illegal immigrants negatively impact everybody from an economic stand point and they prevent our capitalist system from working as designed. The only thing businesses are worried about is their profits. Capitalism does not guarantee any business a profit and hiring illegal immigrants to avoid raising labor rates to what legal citizens are willing to work for is unethical business at best.