Why The Ads In Paid Apps ?

[SuperDuper]

I am losing my mind. It seems many of the games/apps I purchase these days still include prompts to buy more of the developers/publishers products. This even happens in many cases through updates. I understand the economy is poor, but this frustrates me. I paid, let me play without being bothered.

I don't review many games, but I might start reviewing games in which these prompts to buy other titles from the same developer appears and subsequently mention this practice in the review and adjust my rating accordingly. Any thoughts on this?