Its usually cheaper to give everyone a small amount of money than it is to set up and pay a whole department of civil servants to figure out who qualifies and who doesn’t.
Also the poor and disabled suffer disproportionately when you start putting strict restrictions on financial aid. Just look at universal credit in the UK, in trying to save money/protect against the boogyman of welfare queens, they government has unqualified assessors trying to fail people even if they have serious disabilities.