They buy to see what it is and then request a refund within 2 hours. However, it increases the number of downloads, even if they return it
But even if they really sold 1 or 2, it would be worth it. It's an app that takes place in 10 minutes.
Maybe another takes weeks or months for an app that will not even produce 10%
Google Play gives you the ability to create codes to receive the app for free. You can distribute codes for promotion.
Maybe you make 100 of them and give them to your friends to allow them to brag and in return they will make a positive vote.
The developer can download for free, The credit card will only receive the request, but I will not be charged.