Because the church was the community and the community shunned them as a group. Churches and organized religions lead to group think and in this case that group think was directed toward a deeply hateful purpose.

I have my own personal issues with religions involvement in politics on the modern stage, as well as the general concept of a prosperity gospel and the ills it forces on those who already have so little but what happened to that family is deeply disappointing and stabs at the core of me.