Why are congregational churches white?
I don’t know if there is an actual answer, but my response, and this is only my opinion, is: for the same reason Baptist churches are black. Congregational churches (Protestant denomination in which each church is self-governing) tend to be low-key, have services that follow printed programs, and whose senior members often pay as much attention to the business end of running the church as to evangelical concerns. From what I’ve seen, blacks prefer churches where they feel free to be very expressive and in fact become an integral part of the service itself and would be uncomfortable in a setting that restricted congregational involvement to that printed in a pre-determined program.