For-profit businesses that have no relations to religion should not be able to declare themselves a particular religion:
1) Workers may not be of the same religion.
2) If the business tries to hire just Christians, equal employment comes into place, so they can't do that.
If the business is related to religion, then it still shouldn't. Let's say a business prints Bibles and wants to hire people. 5 people apply, but 3 of them are non-Christians that need a job. Since the business is for profit, even though it is religious in nature, they still would have to hire the non-Christians if they fit the criteria for the job.