Using an activation code that you did not pay for is software piracy. While EA rarely pursues individuals for a $10 game, your ISP might flag torrent downloads, and you expose your machine to legal threats from anti-piracy trolls.
Digital Storefronts: The game is frequently on sale for just a few dollars on platforms like Steam and GOG. Purchasing here ensures you have a clean, working copy of the game that stays in your library forever.
The hunt for a free "Zuma Revenge activation code" is a nostalgic wild goose chase. In the time it takes to sift through spammy forum posts and avoid fake downloads, you could have spent $5 on Steam and been playing within five minutes.