There absolutely is both for tax purposes as well as for legal religious exemptions.

You can't just arbitrarily call your house a church to avoid paying property taxes. Government authorities have to make decisions all the time over what they deem to be a legitimate religious organization.

You obviously don't need a license or authorization to engage in otherwise legal religious practice, but as soon as you want legal exemptions, the government most certainly has a say. And the ritual consumption of otherwise illegal drugs couldn't be a more perfect example.