Well, the game at least makes the effort to make the refugees a more even moral spread. Some of them are parasites and rogues, like Aradin who turns out to be a real piece of shit...
Aradin's not a refugee, just as an aside.
He was as much a refugee to the grove after Halsin was captured as the rest. He had nowhere to go to as he was stranded there, the Goblins had them corralled, and he was as much a resource drain on the druids as any tiefling.
I think JandK means Aradin was not a refugee from Elturel, but was instead a mercenary in a tight spot.
He's also a Baldurian, right? Coming from Baldur's Gate as an adventurer with a "contract" to get a relic.
(i get a kick out of the way that contract is more like a leaflet once you get to bg, lol. aradin's glad to be rid of it, as if it was some special legal document, as opposed to be a dime-a-dozen print job scattered about the city)