mooooooooo

The pay difference can be explained by Indian nationals not demanding as high a wage to do the same work. Is it morally necessary for a company to pay groups of workers the same, even if they would accept different wages? Perhaps.

Is "culture fit" illegal?

Let's say that an Indian manager hires more Indians because he feels like they are easier to work with. Now, he doesn't just hire Indians, but he is statistically more likely to do so over a large quantity of hires. Is that against the law?