That is a good point, and there are only 2 reasons a game app would be free:
1. It's a crappy game. 2. The free version is addictive enough to cause people to buy the full version in order to continue onto the next level.
I tried all the free Cascadia game apps, and there are quite a few that have pretty good potential for generating revenue. I am sensing a pretty positive Q3 report, one that could surprise a lot of people... we'll know soon enough!