As Strand noted, they're not even in the list of games on sale. If that's how it's supposed to work, it seems counter-productive. If it doesn't show on the sale page, and you only check for sales, how would you ever see it? I would be interested in the East India Company, but if I'd just logged onto Impulse and checked the sale page, I'd have never seen it was on sale. I on;y found out because I stumbled across it here.
*edit* I see it does show in the banner, but... I almost never pay attention to banners.
*2nd edit* Strand, in the banner on Impulse it shows Age of Booty and Scrapland as 30% off, not 50%. I believe that was just a typo on ID's part.