[Qwertious]

>This is precisely the issue that the social sciences often miss because it's an ethical, not scientific, question.

You're completely missing the point - if it doesn't get results, they're not going to do it regardless of whether it's morally acceptable or not. Businesses care about results.

[omginternets]

With all due respect (truly!), you are missing the point.

The point is: scientific arguments fail to convince because the issue escapes the scientific domain. The question is not "do we naturally tend to do X, Y or Z", but rather "at what point and to what extent are we ethically obligated to seek out people different from ourselves?"