Upon further inspection, it actually looks like the only transactions they're processing are the ones from their own wallet. The entire TX history looks really suspicious to me.
E.g a very recent TX with some ETH going out: https://etherscan.io/tx/0x5a282187181907995b37c0df1888dfe364...
That being said, does FTX even allow custodial ERC20 transactions? I'd be surprised if they did.
Upon further inspection, it actually looks like the only transactions they're processing are the ones from their own wallet. The entire TX history looks really suspicious to me.