Since they're just ads for other things by Rovio (which, if I were a big Angry Birds fan, I'd personally be happy to see: I usually like to find out other stuff made by those who make stuff I like a lot), I wonder if they could've mitigated the backlash some by making it easy to choose not to see them again.<p>Anyway: convention is that paid apps don't have ads. That's tough to overcome, and everybody gets <i>more</i> pissed when the big guy seems like they're taking advantage of their position.
The title is inaccurate here: they didn't add ads to the paid app, they added recommendations for other games made by the same company. The original title, with "ads" in quotes, is more appropriate.