I understand the distinction you are drawing, Ned, and I agree that it is difficult to maintain a psychological/philosophical view of human flaws in the case of an institutionalized practice that seems closer to propaganda, i.e., lies in the service of a "greater truth."
No doubt most institutions of belief harbor both knaves and fools as well as the ethical and sincere.
Still, group psychology is, if anything, even stranger than the individual. Examples of a diverse population turning on itself murderously after decades of apparently friendly coexistence abound--I'm sure those who became mobs felt the "rightness" of their conduct and the "truth" of their beliefs.
That people can hack each other to death over ethnic or doctrinal differences in the name of a divine being who ostensibly forbids such conduct demonstrates how deeply bad faith can go.