1. Most traders are too lazy to transfer assets to another broker and get used to another trading platform.
2. I am sure most traders here are trading equities, not futures or options so they won't be able to leverage enough to lose more than 100% with a 30% move.
3. Lastly, most ET traders are not trading big enough to really incur much of an exposure fee anyway.
You might be surprised....I am curious if/how IB measures exposure fee's on futures options since the futures market is settled each night my guess is if you duplicate your short SPY trade using ES options they would NOT charge the fee??