Because they met the legal requirements to be a tax-exempt religious organization, and despite your apparent belief that you get a vote in what other people believe and how they live their lives, it's not for the federal government or anyone else to decide on the "legitimacy" of someone's religious beliefs.
It would be incredibly nice if leftists ever came to understand the true meaning of the phrases "No one asked for your opinion" and "No one cares what you think".
Apparently, you are so ******* stupid, you don't even see the contradiction in the two bolded statements.
Apparently YOU are so ******* stupid, you don't even see that the only "contradiction" exists in your head. Your inability to understand something doesn't make it incorrect.
Since I'm feeling charitable, I will explain it for you one more time:
IRS tax-exemption does NOT confer "legitimacy" on a religion, any more than a marriage license confers it on a relationship. Only liberals think government sanction equals legitimacy, because only liberals worship the ******* government and think the world revolves around it.
Tax-exemption confers one thing, and only one thing, on a religious organization: tax exemption. And the IRS determines one thing and one thing only: whether or not an organization
which chooses to apply for tax-exemption meets the requirements to receive it. Should you ever pull your head out of your ass long enough to actually FIND those requirements and read them, rather than sitting around on your dead ass, whining for someone else to tell you what they are, you will see that NONE of those requirements involve the IRS judging the actual beliefs of the organization for their validity. Also, the IRS does not choose who will or will not apply for tax-exempt status. Any group may apply which wishes to do so.