To respond to your edit, my guess people downvote you because you completely misunderstood the situation and did not care to correct you when the situation was explained so many time, and probably think you're disingenuous.
I think you're not, so I'll try to explain:
When the technicians I work with install a new windfarm/gas plant router to connect them to electricity markets (they probably do other stuff but my job is the software part of networking, so I only know about that), we could hire a local contractor with CISCO cert, and it would certainly be cheaper than fly out 20 workers to Argentina, Australia, Romania or Mexico. We don't, because our employees will use the same technique, the same methodology each time, for every client, and we will never have to guess how the installation was done, because we know. You can put a price on trust, but it's really expensive. If we had plants in the US, I guarantee we would do the same, for the same reasons, unless the government bought our trust (which is basically reimbursing our losses if the plant fails because the installation wasn't done as our technicians would have).
Unless we hire permanent workers as we did in Romania because we took a big market share there, training someone to follow our procedure, highly personalized, for a week to a month of work is just not worth it, especially when so many specialties are needed for like one hour on one site. We do hire locals to run the day-to-day operations, but the installation, it's just not worth it. Better to fly a tech team every 5 years, that stay like a month, look around, fix shit, then leave.
For the second part: you misunderstood the situation. The workers were only there for the installation of the assembly line (and probably training for the B1s), not to work full-time.
Note that at least some of the workers have basically the same job as our technicians, network engineers, people I work with a lot and that I really respect. To see that parade, picture and video of them being taken on purpose while in chains (not handcuffed, in literal chains) to humiliate them on purpose, and seeing so many Americans cheer in front of that makes me hate most of you. Sorry, I know 'not all Americans', only a third, but still. Cheered because workers are publicly humiliated. That's what your country looks like from the outside.