It is the immigrants that are unauthorized, not the facilities.
The facilities are needed to house and keep the “unauthorized immigrants “ while waiting to process them.
They have illegally entered this country and by law need to be processed and if needs be returned to their own countries.
If they want to come to the US, then there are plenty of LEGAL and Authorized ways they can do this!
Stopping funding for the facilities is not the way to help them or us.