Companies I've worked for, Virgin Games (run by a British immigrant), Shiny Entertainment (also run by a British immigrant and seemed like > 50% foreigners). Naughty Dog had at least 5 or 6 foreigners of 30 employees when I was there. The owner even made a point of showing us the first hire's salary and asking us if we knew any locals that were qualified for the job that wanted the job so that he was sure he was above the law.
A few years later that hire went on to co-found Ready At Dawn which was founded by 3 immigrants. I have no idea how many of their employees are foreign.
I have seen one company, Interplay, abuse their power over a foreign employee by threatening to pull their visa support for him before if he didn't do X (I think X was stop some un-work related outside music activity). He ended up marrying his local GF and then got the hell out of that company.
The company I currently work for, as far as can tell, has a similar position. We'll hire anyone that applies that can convince us they can do the job. Finding them is hard. There may be tons of qualified people but either they aren't applying, they can't write a resume that makes it look like they're qualified, or they can't convince us in the interview that they are qualified.