No, we'd be spending far less under what I propose.

No accommodation in the public school system at any point.

Cool, let's create a huge, poverty-stricken demographic with no education whatsoever. I'm sure that will work out swimmingly for the Americans who live around them.

No accommodation in the courts system, except for deportation hearings.

Cool, so we should let humans, even though they are criminals, have no access to help if raped, robbed, assaulted, murdered, etc.? I'm no bleeding heart, trust me- but that would be super fucked up. Does that apply in reverse? Do we also spend no money prosecuting crimes THEY might commit on others? You know, since in your version of events, we knowingly created a starving, uneducated, massive population of desperate people.

No accommodation in the driving license system.

Well, if you want to have your body maimed in a car wreck by a drunk Mexican or something and then have zero ability whatsoever to find out who they are after they flee the scene ...

No accommodation in the employment or tax system.

Again, let's create a starving (nutritionally and economically), desperate population who will endanger others. Oh and let's not at least get some tax money off them. Cool idea.

Etc.

Massive excise taxes and repossession for anyone illegally employing illegal immigrants.

Agree here. Employers should be penalized for hiring them. This could be helpful. But do we get to also penalize our government for letting them in?

Hell, we might come out ahead on that alone.

Yeah ... illegal alien population must be hovering around 30million by now. We should totally make sure they can't eat, work, or get anything that would make them not ghosts who can wander around and do what the fuck ever to who the fuck ever without fear of identification. Unless your plan includes a magical, peaceful mass deportation ... that's gonna be a bad time, bro.