I think people are pretty ignorant of what the rules are and what the situation on the ground is (just try shipping homeless people from LA to pick fruit on farms in the central valley and see what happens)

On the other hand the "follow the rules" thing is pretty strong and you cannot fight it and win.

I got pretty mad riding the subway in NYC paying the toll and seeing turnstile jumpers hold the emergency door open to let people in.

There are all these rules you have to follow big and small that you don't agree with that you either follow resentfully or you disobey while taking some real or imagined risk.

To take one stupid example I've been through multiple toilets in one bathroom and haven't found one that flushes reliably. It's easy to blame the regulation in New York State that a toilet has a maximum flush volume and you'd better believe I am thinking about going down to PA to get a toilet and see if I have better luck. We all have these things that we could be resentful about and one thing that keeps it in check is knowing that other people are subject to this too: when we see people who seem to be "cutting the line" it makes our blood boil.

Now you can say it is not what people think, like really the chicken houses that hire 600 illegal immigrants wouldn't want to hire legal workers because then they'd have some protections, and that's all true. But the iron law of political psychology applies and if you want to change attitudes it would be a big help to move immigrant workers out of the shadows or to cut back on rules that make people resentful with little benefit.