The author would save everyone’s time if they simply checked the box that says “contains in-app purchases or subscriptions that cost money”Apple has a way already to signal this. ^^ Otherwise, the non-free aspect is easy to miss, it is there in the 9th paragraph (!!) of their description.
If the application has in-app purchases, then next to each "Download" button there is the inscription "In-App Purchases". This is how the AppStore works, and of course, the app developer cannot break it. In addition, I indicated purchases in the app description. There is also a list of in-app purchases at the bottom of the app page. Thus, information about in-app purchases is duplicated three times on the page of this application.But your review will stop those who are not going to buy anything anyway. And thank you for that!