Apples to oranges. Card networks have more than three stakeholders to work with per transaction, apply fees indiscriminately from milk to digital music subscriptions, and operate at truly staggering volumes.
So if within their own industry Visa and Mastercard overcharge like crazy, especially when they can, what makes you so sure that they’re a good counter example for a completely different industry? Especially when competitors seem to be charging a very similar rate for a similar service?
That being said, it is a fair point when you consider that retailers and other similar product middle men tend to charge 1-3%, but it’s important to also consider that Apple position’s itself as a luxury product and brand where 30% markup isn’t actually out of line.