What Role Do Gas Fees Play in Transaction Ordering on Proof-of-Work/proof-of-Stake Blockchains?

Gas fees are the payments made to network validators or miners to process and confirm transactions. On many blockchains, a higher gas fee incentivizes the validator to prioritize that transaction for inclusion in the next block.

This priority-setting mechanism is precisely what front-runners exploit. By offering a slightly higher fee than a target transaction, a front-runner can ensure their trade executes first, profiting from the subsequent price impact.