Nah, credit card fees are like 1.5 to 3.5%.

Country dependent, in the EU there is a legal cap of 0.2% for debit and 0.3% for credit card transactions.

Interchange is $0.35. On small transactions, that eats up a lot.

i dont believe any of those companies take anywhere near a 20% cut per transaction

Also, iOS App Store and Google Play Store aren't just straight payment processing, they are Merchant of Record.

That's incredible, so Stripe at 3% plus $0.30 per transactions must be losing money hand over fist!