A few people quite fairly said it would be tough to make a call on the incident given the limited account I'd written in the original article. Others pointed out that you could probably draw an ethical distinction between the Blacksmith's decision to: a). accept a tip, and b). keep the gold gained from vendoring the 2H mace (and I think this is accurate, although it does raise another question. More on this in a bit). Commenters also observed that, the ethics of the Blacksmith's actions aside, you wouldn't necessarily want to be a repeat customer of his for reasons that hadn't been articulated in the original piece.
So behind the cut is a more inclusive look at the issue, a little more background on what happened, and how other players responded to it ingame.