The right thing to do (in my opinion) would be to deduct any fee you think is worthwhile if you think that customer service sucked. So if you were entitled to 100 BTC, and got 200, and is pretty angry with the whole ordeal, I think keeping 110 BTC and returning 90 BTC would be a good way to go about it.
I think taking the extra 10% if that's what one is rightfully owed is OK, but I don't think deduction of an inconvenience fee is appropriate. Should the person who has to eat that fee (possibly another shareholder?) collect a fee from you for his inconvenience resulting from you keeping his money?
Is deducting one possible? yes... Deserving of a scammer tag? probably not... Consistent with the notion that governments are bad and that coercion by force is an unnecessary intrusion onto our freedoms?... no, doing this sort of makes the opposite case.
Act upon your values - if your values are such that anything you get your hands on, you get to keep, well by all means, keep the extra coins. Thank Jesus for them if you feel so inclined (referring of course to the deity figure, and not suggesting that the guy who gets stiffed for them will have the Latin-American given name "Jesus")
Hi casascius,
I don't hold any money with GLBSE, but if I did, depending on how angry I was with everything, I might have kept a 10% fee for the emotional distress, I wouldn't have kept twice the amount though. People need to learn, if they act as doucehbags, it should get back to them in one way or another. Neither me, nor any customer would ever be personally responsible for any other customer GLBSE may serve, that's the responsibility of the operators. If they make users angry enough, and then make a payout mistake, I won't blame customers that keep a 10% inconvenience fee. I don't see it the way that other customers would suffer from this, I think the operators should pay this out of their own pocket.
You could also think of that the customer could chose to keep all of what he received from the double payment, so returning half of it minus 10% is far better than being severly out of pocket (for operators), which would be the case if the customer selected to return nothing. I might as well have returned everything that wasn't meant for me, I don't know - it depends on the situation and how I felt about it.