This is beyond either GDAX or Bitfinex but that is the current reality of making transfer via btc. The amount I'd quite high but because of how fast they want it to confirm, they just apply a blanket amount as charges which happen to be 30% of what you are sending. Just like Paxful that would charge you 0.0008 irrespective of what you are sending and some other exchange too. Bit what happened here was you were not told whether to include the transaction fee in what you are sending or they must have notified you but you didn't note it before confirming it which they then deduct from the amount being sent. Hopefully this would be reduced when transaction fees gets lower but for now, there is nothing you can do about it.
