"Those "small" companies include major construction companies"
All the examples I've seen involve small subcontractors who hire illegal aliens. Large construction companies rarely hire all the workers directly and contract our most of the work.
Same thing with cleaning contractors. Where Wal-mart got in trouble is that some of the executives apparently knew their contractor hired illegal aliens. I never heard how that turned out. I heard it was settled, but it was never really clear how much they know and how sure they were of the information.
All the raids illegal immigrant raids of employers I've heard of involved subcontractors. Large companies make too big of targets for enforcement and have too much to lose. Small contracting companies can simply disolve and reform under a different name if people start asking too many questions.
I don't know much about large agricultural companies and how they work. Things could be different there, but I haven't heard of any large scale arrests, please point me to information on some of them if you have it.
I spoke with the builder who built my home about this. It seems like most of the roofers and a good number of the framers around here don't speak english.
The builder says he simply doesn't have much control over who the subs hire. If they do the job well, they get paid, if they don't he finds a different contractor. He doesn't have the authority to investigate their employees.
"Give it a break, 11-15 million people is the stuff of major employers."
Do you understand the absurdity of that statement? The majority of Americans don't work for large companies.
Wal-mart is the largest employer in the US with a total of 1.2 million employees. However their business supports a much larger number of other companies that hire cleaners, shipping companies, companies that produce things sold by Wal-mart, importers. Some of these are large companies, but others a lot of them are not.
If you look at most any large industry you'll find a lot of contract labor and subcontracted work.
Your assertion that they have to work for large companies because there are lots of them isn't supported by the facts. It might be true, but where's the proof? The evidence I've seen points toward lots of small companies and lots of contracting companies hired by larger companies.