If that replacement can serve the same purpose, and give approximately the same value to the company, why should the native and/or higher-waged person expect to have priority?
We've compromised as a society and said sure slave labor will exist but not in the US, if a company wants to benefit from the infrastructure and educated workforce and culture and benefits that American society has developed they have to be decent corporate citizens and treat workers with a modicum of respect. You're suggesting bringing slave labor here, I'd suggest rather we sprint in the opposite direction and ban it everywhere through e.g. making the import of goods made through slave labor a criminal offense.
In practice, this depends on a number of factors being aligned correctly and an organization being tuned to the idea of remote work. Especially if the deliverable of the IT job in question is part of the core function of the organization.
Exporting with long-term net success (in savings or quality or both) is what's difficult.
Why should Disney expect to keep that monopoly privilege and control if the public could still get the same benefit from someone else?
Why should the laws of a mostly free and mostly democratic society matter?
If you're playing a game, with rules, why can't you just help yourself to extra tokens and change the die rolls, and look at other people's cards?
Because the other players will frickin' kill you, that's why, you lowlife cheater. The rules are there so that everyone has a reasonable chance at winning, even in the enhanced-difficulty challenge modes.
For a variety of reasons, some supportable and others abhorrent, the rules-makers decided that unrestricted immigration would someday turn the country into an exploitative, stratified, third-world hellhole. So far, none of their grandkids have had the balls to throw open the gates and fill up their ancestors' neighborhoods with scary brown people with their thick accents and weird foods. Deep down, we're still tribal animals, and the law reflects that.
So the reason is that we follow the law, even if it is stupid, racist, and xenophobic. That's why the citizen gets priority over the foreigner. If you don't like it, you change the law for everyone instead of cheating it just for you.
We know that Disney knows how to lobby for changes in the law. And we know they can get stuff passed that would make ordinary people want to vomit. So why wouldn't they want a new law allowing a specific business category--one so narrow that it could only reasonably refer to Disney and a few other big companies--to import unlimited numbers of foreign workers at below-market wages?
It isn't about the law being the law, but everyone being equal before it.
Besides that, a bad law can be changed to be better (in theory). We can do that via the sanctioned legislative process, or through mass civil disobedience.
These companies that are cheating various provisions of immigration law aren't doing it as a protest, but as a means to make a quick buck from a bunch of people who can't effectively seek redress.
The laws should be good for the people in the country.
Or have we entered an era where hereditary property rights are so much more valued than a citizens rights that we can no longer even see the analogy here.