The answer is simple. Because parasites can't feed on other parasites. They need a host(whitey) upon whom to feed.
And theres a lot of white self hating dogooders who believe that flooding western society with third world trash somehow is a source of "strength". It will be our downfall.
Here's what should be going on.
www.gobacktoafrica.com
https://www.bbc.com/news/world-africa-49394354