A legitimate religious organization does not use physical, mental, emotional and financial abuse to maintain membership. Nor does it function as a conspiracy to threaten and intimidate others. A valid religion informs people of church doctrine and beliefs before they make a commitment to join. A religious group with even the most basic ethics does not use its constituents as slave labor to reproduce and perpetuate its teachings.
It's pretty simple. American tax codes are wrongly benefiting and empowering the unethical, potentially illegal, and most assuredly uncharitable activities of an organization using "religion" as a cloak.