[smcl]

I'm not even sure we can assume Stripe won't go away, and Paypal has shown itself to be anything but dependable (sure it'll accept a payment but will you definitely get the money?)

Edit: Sorry I know those were just two examples - I'm not trying to refute your point

[astrodust]

They're bordering on "too big to fail" at this point, but if they did go, they are just a payment provider. Switching from Stripe to PayPal to Square or whatever for credit card processing is a heck of a lot easier than switching from the Apple App Store to your own hand-crafted store.

For example, you can bang together your own store with Magento, Spree, or any number of other ecommerce store kits and pick one or more back-ends without a whole lot of sweat. This presumes you know a thing or two about web development and security, which is not necesarily a given for any group of developers. If you do know that, the difference between Stripe or PayPal is a few lines of configuration and API keys, if that.