The Sims 3 EA DLC Unlocker works by modifying the game's internal settings and configuration files. It appears to use a combination of techniques, including:
The "Sims 3 EA DLC Unlocker" persists because EA refuses to make their legacy content accessible. While The Sims 4 offers a free-to-play entry point, Sims 3 remains behind a $400 paywall. sims 3 ea dlc unlocker
And below that, in tiny, blinking text: