Why Hire Adventurers?

[PhoenixPhyre]

Or, alternatively, "Adventurer" isn't a Job in itself, so much as a catch-all term for a bunch of different jobs with similar skillsets, and so people who drift between those jobs as employments warrent are "Adventurers".

Adventurers are Guards you hire to protect your caravan, they're Exterminators you hire to clear the ghouls out of the town crypt, they're Mercenaries you hire to fight off goblin raiders, they're Bounty Hunters, they sell all sorts of secondhand weapons and armor from enemies they kill, they sell wolf pelts and exotic treasures.

These jobs have overlapping skillsets, so why is it odd that a group of people with those skillsets might drift between these different jobs as needed?

Exactly this.