@dstan @BenRiceM Yeah, the 2,9% is generally what you see quoted just for the credit card processing, which is just passing through on its way to the credit card company.
At 3%, Apple has basically no margins, although I wouldn't be surprised if they get a slightly better deal purely on volume, guarantees they're able to give the likes of Visa and Mastercard, etc.
And that's before you get to the fact that Apple likely eats the losses on chargebacks, disputes, and so forth. Small transactions having the least margin in total.
It sounds like a lot of money in aggregate, but I bet it's way less profitable than most folks assume.