There's a whole class of sh*t-software that only exists (and is profitable) because users subscribe to them and then forget – primarily because the subscription fee is charged as "Apple" on their Credit Card. I wonder what's gonna happen with this type of scam.
If through Apple it is easy to cancel and all subs are listed in one place. If done through third parties directly the scammers will not make unsubscribing easy and it will not be as easy to find out where you are subscribing. Thus I expect the scamming to increase.
It's also Apple's specialty to create false dichotomies and shit sandwich bundles: it's either the 30% cut or daylight robbery. No third option (in reality PayPal is more consumer-friendly and allows managing subscriptions in one place from more than iOS).
The whole App Store model is a false dichotomy between the 30% cut and Disney-like moderation vs raging malware that will take down the whole mobile network. No third option (so you can't have Fortnight, or any app showing a nipple).