Same with hiring Illegals to mow our lawns and do craftsman work. I got on to one of our family members sounding the horn about Illegals yet they hire them.
I lived in N.CA from '74 to '04 and there was a law that prohibited you from hiring them if the work exceeded a dollar amount and you were supposed to hire a licensed contractor. I forget that dollar amount and the subsequent fine if you were caught but as I recall the fine was less than the money you'd save by hiring several Mexicans to lay brick or tile, do cement work, yard work, etc. Some were likely green card, some born here, but many were likely illegal. It didn't appear to be an issue with those that had work for them to do....and most of then did very good work.
As I recall the licensed contractors lobbied the CA legislature to enact the law but like all laws it has no teeth if not enforced. I also don't recall LEO doing much to roust the dozen or so that would be standing around the Home Depot entrance driveway.
They likely had bigger issues to deal with at the time and I can understand that....like actual robberies, carjacking, rapes and murders.