I know it's the cool thing to run into a thread, both barrels blazing and start shooting at EA, but you're not being charged for these. The Legendary cards are randomly inserted into Gold and Platinum card packs.
If you actually go to the site, and you know...READ before reacting, it's clearly listed in the description: "Earn coins to buy new cards or card packs through your performance on the field, acquire new cards through the auction block, or purchase card packs through the in-game store."
So yes, while there is a purchase option for those that don't want to put in the time to earn the coins to "buy" the packs of cards; you can acquire these cards just by playing the game.
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Thanks for posting the info, Steve.