The spoils for PvP are 5% of whatever the coin and credit maximum your enemy has.

Then remove 20% of that 5% to calculate of what you will take with you. (you will take 80% of 5% of whatever your opponent has)

That is a measly 4%.

The reason the OP lost so much was not because the loot % was high. it was because he had with him so much coins and credits that he didn't bother to spend.