Is it just me or does this seem like it might be a blow back at Hey? They got their app into the app store by creating temporary trial accounts[0], but they still don't bill through Apple or accept signups through the app. This seems like a way to force them to do so.
It feels to me more like a publicity grab by the app developer. “Hey” got an enormous amount of attention and 10 times the number of sign-ups they were expecting because they picked a fight with Apple and screamed about it really loud. Not surprising to see more developers try this approach.
[0] https://www.theverge.com/2020/6/22/21298552/apple-hey-email-...