The thing is that EA has been run in recent years like any other company and for good reason, traditionally Game companies were just like any other company in regards to how they should be managed. For EA, sales are a bad idea because every sale is lost revenue. This is a very physical minded sales mindset though. The store sells the game at full price, the net profit on it is not only known, but was planned for and other future investments (new game dev) is planned based on that number.
But if the store sells the game at a discount, there goes the profit. All that's been achieved is an increase in awareness of your store and a reduction of inventory.
But none of that matters to Steam, because their inventory has NO COSTS relating to sales aside from server costs (this is very simplified). They don't spend millions on producing discs, boxes, shipping, store rent, etc...
So sales make damned good sense from Steam's point of view. Especially since people can't trade games. So you got Portal for free. But you missed Portal 2 at the sale. So you buy it full price afterwards. Or you tell friends about it and they buy it for $9. Either way, Steam's making $$ off those sales. From the oldschool EA perspective, each of those sales is loaded with opportunity cost (the money that could have been made in a normal sale). From the digital download mindset, those sales are more profit. That's the fantastic thing about this model. When you're product is 100% digital you can play with the price charged for a product in order to boost sales without loosing any money. EA just can't get their heads around that. Look at how they've run their digital stores up to now (Sims 3 especially).