: Gaming companies (like Riot, Epic, or Steam) run these lists against their own databases to proactively reset the passwords of any accounts that match the leaked credentials.
: Services like Have I Been Pwned ingest these "bases" so users can check if their own email has been leaked in a specific dump. 100K HQ GAMING BASE BY Old_Deep.txt
If you are interested in the of how these lists are handled by security professionals, here is how they are typically used for legitimate defense: : Gaming companies (like Riot, Epic, or Steam)