Liquidation contracts and Arbitrage contracts do check the caller and would not allow to be executed by non-approved senders. This raises the bar, so that you can front run only contracts that you can implement and deploy.
If anyone could just replace an address and execute a profitable transaction by being first on existing contracts, surely miners would be doing it already, no?
If anyone could just replace an address and execute a profitable transaction by being first on existing contracts, surely miners would be doing it already, no?