This is purely my speculation, but I have a theory on how they get those jobs. Ul'dah is the city that has the most religion in it. LL and Gridinia do not mention the gods like Ul'dah does. Anyways, Ul'dah has two big temples in dedicated to their twin god. Both the Monk and Paladin are religion themed. Monk referring to a type of priest that lives in a monastery and trains their body and paladin being a holy knight for the church. To tie in with the faith of Ul'dah, the faith a Nald'Thal could be recruiting defender for the city from two of the biggest resources of adventures, The GLA and PUG guilds.
Like I said, pure speculation.