You seem not to be aware that the U.S. government, as well as the state governments, have both the constitutional support--and, in some cases, requirement--to provide some of the economic and social supports that you are calling "charity". 


And good luck trying to keep Catholic charities from seeking grant-funding. Catholics don't provide enough of the funding to get the job done. Never have, never will, never can. Which is not to say that Catholic charities have not done more than any other sectarian or private sector organizations.