I think they just couldn't be bothered to make a new one because they already had that one. I wish they had given him something more interesting at least for the ending where he goes to the Underdark. Drow armors look so good on him.
I think all of them wear outfits that are supposed to reflect their standard friendly paths of life - though why Cazador-alive-Spawnstarion and Adventurer-Spawnstarion wear the same stuff, I don't know. The description makes most sense for someone on the road with the repaired shoes and all.
