I've been wondering how do DEXs make money. I know some of them like uniswap and airswap supposedly don't take any profits from trades. But are all DEXs like this? I read on Kyberswap FAQ that the user pays a 0.1% fee on succesful limit order transactions. But it doesn't say if this is an aditional fee or if it's just the normal ETH gas fee.
Does anyone know if other DEXs take a comission on transactions as part of their business model? Or are they all non-profit?