So would human downloads, too. Mass audiences do not buy apps. They sometimes buy in-app purchases after installing them, but in terms of games, it's mostly the 'casino games for children' genre that make 90% of that kind of revenue.

Also, all else being equal, earning potential of paid or subscription apps on Android is usually an order of magnitude less than on iOS, due to the self-selection effect of people who buy $1200 phones tend to have more disposable income than someone who buys the median Android phone which costs much less. So, trying to sell a paid casual game, especially on Android, is not going to pay the bills the way an ad-supported free app would. Sadly.