As a "religion producer"*, it was easier to do and required not mastery over PR but mastery over slave labor.
* I actually read that term in an article years back about religion's place in the economy. Economists found that religion pulled people away from producing more, but also gave them essentially a product they could believe in. I think it was in Time but I'm not sure. I'm pretty certain this religious product in particular did not help the economy at all.