Because immigrants, even illegal, ones still pay taxes ie sales tax.
More than 50% of people in the US do not pay taxes because they don’t earn enough to be taxed.
Also, if an illegal has a broken arm your position is they should be denied healthcare?
https://twetch.app/t/1ecd4239e78eac7dfc3c64d83f3791cf9f7499a60eafb46fe6196669a99ba1e8