Why is "church" (specifically) built into the onebody product? The software would seem to be organization-agnostic, suitable for any community group. "Church" is certainly a reasonable target/majority use case for marketing, but it seems strange to exclude other cases where a group of people come together in a buildng, take classes, plan events, etc, where the software could work fine.

I agree somewhat, though OneBody does have church-specific features built-in, such as favorite bible verses and prayer requests etc. It is specialized for church communities, though you can turn that stuff off and use the software as a general community social network if you want.