Racial harmony?
Not immoral at all, what a boring world we'd live in if we were all ethnically homogeneous. So long as people live by the law of the land and don't try to change the rule book or over step the mark and break moral codes then yes I think it can be a great thing. Unfortunately we have problems with this in many parts of the developed world when we take in mass numbers of refugees from poorer countries etc. I'm not saying we shouldnt help but we need to be careful with the numbers.
As long as you respect the ways and laws of where you go