Apple has rules and regulations in place for all sorts of things, but especially for the App Store. Developers must follow those rules if they want to keep their app(s) in the digital storefront. Sometimes those apps only get discovered for bypassing the rules, either in big ways or small, only after the app's been available for some time. (The App Store review process doesn't always catch the offenders.)
Amazon got Apple to pull the Fakespot iOS app from the App Store