It's great that we agree that all the poor and needy are deserving of help and support.
But how do we do that at scale?
Because your church (let's say it's in Utah for convenience) how does your church in Utah help the poor in Alabama? Because the churchs there are in poor communities. And the poor, even if they do donate 10% of their income, can't generate enough pooled money to help everyone.
And because they're poor, they can't take the time to volunteer to help staff the charity programs. they can't take the time off from their 2 or 3 jobs.
What do we do?
How do we pool enough money, resources, and people to make sure that everyone gets help?
Now imagine a privately funded non-profit. How massive would it need to be to go into literally every household in this country to verify need and distribute it.
But you know what already exists that already has access to that information AND is able to reach literally every community in the country? The federal and state governments.
AND can't deny people based on their religion. So, as an example, a church in Alabama can't declare Mormon's as non-Christians and thus won't spend their money on Mormons. Mormons get just as much help as anyone else.