It sounds like the order you tried to place was hedged which would mean that you got the same dollar value amount back in BTC to the value of the item you tried to buy. The value of BTC fluctuates all the time, hedging protects buyers against the volatility of the currency, does the dollar value you received back in BTC equal the value of the item you tried to buy? I think you will find it is therefore you were not shorted on the refund.