Steam sales are working for someone.
In January, Steam reported a concurrent-user high of 5 million during the 2011 Holiday Sale, along with more than 40 million accounts. Today, Steam has an excess of 50 million registered users and more than 2,000 games for them to play.
And, at least for now, some of those games are super cheap. Don't think of the Steam sales as blatant, bold ploys for your user numbers; just think of them as win-win situations.