I would argue that this pattern is an irrationality that must be corrected with force [1]:
When faced with a choice of selecting one of several available products (or possibly buying nothing), according to standard theoretical perspectives, people will choose the option with the highest cost–benefit difference. However, we propose that decisions about free (zero price) products differ, in that people do not simply subtract costs from benefits and perceive the benefits associated with free products as higher.
That is, users systematically spring for games with lower cost-benefit tradeoffs simply because they are offered for free. While this would be economically infeasible for game developers, they've figured out how to take advantage of other psychological breakdowns to extract revenue. On a larger scale I'm not sure this makes users as happy as they could be.