The catch is who gets the $210 million. The store doesn't put the box on their shelves and pay an employee to run the checkout line for free. The distributor doesn't ship the boxes to the store for free. The pressing plant doesn't make the DVD's and stuff em in boxes for free. WoWhead doesn't run full border ads for games that compete with WoW for free.
For console games - not a perfect analogy because the console maker collects roughly 20% off the top - figures that are routinely cited give less than 50% of the revenue to the developer and publisher (in this case the same corporation). The numbers get much more favorable for direct downloads and recurring subscriptions, which is a big part of why studios like them, especially since they're often serving multiple gigabytes in patches to even the retail customers. This, in turn, is why the high churn rate hurts the game's outlook so dramatically - one of the biggest benefits to the developer to having a monthly fee is that they get a much larger cut of that revenue compared to the initial box sales.
In this context, it starts to make sense why EA is throwing around numbers of half a million subscribers - it's never been stated for precisely how long but presumably a few years - to break even on this game. If they're keeping only half of that initial revenue, seeing box sales decline in both volume and pricing, and continuing to bleed hundreds of thousands of subscribers each quarter, it's going to take a long time for them to break even on even $300 million in total development plus marketing costs. One wonders if the picture would have been different had they gone online only - but I suppose EA's console retail presence wouldn't have allowed them to try such a move.