I work (in Europe) for an American company. All the people in IT we hire in USA are foreigners, they are cheaper. You cannot say it is discrimination on wages because everyone is paid low. The visa system allows the company to pay low wages and hiring foreigners is just a small detail in the scheme.

Anecdotal statistic, in my department all the people in US and Canada hired in the past 10-15 years are from Africa or India. The only Americans or Canadians are the managers, they joined 20-30 years ago and slowly retiring, now being replaced mostly by Indians.

It is happening the same in Western Europe, just with a different demographic.