Can Good People Belong To Bad Churches?

The Mormon Church is certainly not alone is committing atrocities against humanity. Probably the biggest example from the past century is the Catholic Church administration's escape aid to Nazi officials at the end of WWII. In fact, the Catholic Church's official policy of tolerance towards Hitler's regime is a suppressed and shameful chapter of history. And there are more examples. Which begs my question: Can good people belong to bad churches? People can be both good and ignorant; good and needy.