There was an important piece left out of the description of the Church of Satan: it is typically used as a device to test civil liberties and separation of church and state.
If, say, a courthouse has a statue of a religious theme, then by the law of the land, the courthouse must be willing to erect a statue for any religion. Like, say, a statue of Baphomet. Or they can remove _all_ of the religious iconography. That demographics are mostly Christian and so such things are overtly offensive makes it more effective.
So, atheists or agnostics or even people of more orthodox religious persuasion are using the Church of Satan as a vehicle of representation for a strong stance on the separation of church and state.
