It's estimated that there's at least 13.7 million illegals in the USA and American Immigration Council estimates that it will cost $315 billion to detain & deport all them from the USA which is just too expensive, but according Grok it will cost only $81 billion to detain & kill them in gas chambers which is clearly much cheaper solution. The USA also doesn't have to negotiate with the other countries to let them accept their illegals back.
Committing so many racial hate crimes that illegals deport themselves: Priceless