my experience reinforces your own entirely. i live in one of the most liberal and secular cities of Southern California, worked at the city's homeless shelter for three years + still do volunteer work for various outreach programs targeting that populace, and I'd say about 50% of the volunteers we get are faith-inspired Christians, 30% liberal activists (primarily university students), and 20% a smorgasbord of various others drawn there for one reason or another (including myself, a devout atheist).
i do not care for the ideology, i do not care for any religious ideology, but there was a marked difference in willingness to devote time for volunteering and money for fundraising when comparing devout Christians (a minority of those who claim the title) to the rest of the populace.
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