A little more...structured than that, but yes. The Weaver's Guild and other guilds in the city will hire adventurers to guard their cargo, but sometimes there aren't any around who want to take the job.

[Thoughtfully:]

There usually aren't, actually. Something about escorting cargo not being what they became adventurers for. Either way, if I don't have any students or if I have students who want some field work, they'll hire me.