All the goods and services funded by tax revenue (eg roads, police, fire, national defense, public parks, schools, on and on) can still be enjoyed by churches and clergy despite them being exempt from taxes. The point is churches benefit from innumerable public goods while not paying for them. This state-granted privilege creates docility among the clergy who focus their energies on abstractions like spiritual salvation rather than political liberation, life after death rather than life before death. Ruling classes love this. Whatever the Jesus movement was when the Flavian dynasty imported it into the Roman Imperial Cult, it was vastly different from that which Rome instituted and offered for ordinary subjects.