Richard Reinsch has a post at the Liberty Fund’s Liberty Law blog discussing the claim (made here by a number of church-state scholars) that RFRA exemptions that impose significant burdens on an identifiable class of third parties violate the Establishment Clause. Richard agrees with me that the argument is not persuasive. A bit from his post involving the baseline from which one argues about what constitutes an entitlement, and therefore an establishment:

So if a religious liberty exemption requires cost-shifting in the manner of employees having to purchase—let’s be clear for Hobby Lobby and Conestoga Wood, the objection is to emergency contraceptives like Plan B, Ella, and also IUDs, and not the pill—their own emergency contraceptives, then we have an impermissible establishment of religion. As Eugene Volokh has argued, were the exemption to be granted the employees of Hobby Lobby or Conestoga Wood would return to the status quo before the mandate came down and one that many employees of companies exempt from Obamacare for various reasons will stay in. That is, if they want emergency contraceptives, well, then, they’ll pay for them with their salaries.