What is the logic or basic reason for this level of extreme prejudice against people doing basic work in another country? It seems to me that someone working in a country is going to be contributing.
Someone working in another country is doing work someone in the country could also be doing, depriving them of a potential job. That's why you need a visa.
Or rather, enough members of the public believe in the lumb-of-labour fallacy to make these kinds of policies fly.
... and the someone in the country is more valuable than the someone outside the country, because xenophobia.
What? No. Because it's the whole point of a government to take care of its citizens. American gov takes care of Americans, Brazillian gov takes care of Brazillians.