This is what the summary says:
Sales 14.24
Payment Provider Fee * 2.92 (20.51%)
Itch.io cut 2.84 (20%)
Owed to you: $ 8.48 (59.55%)
*There is a discrepancy between your summary and the detail list - they show different values for the payment provider fee.
The detail list shows:
Sales 14.24
Payment Provider Fee* 2.76 (19.38%)
Itch.io cut 2.84 (20%)
Owed to you: $8.64 (60.67%)
Initially I wasn't requesting payouts because I thought on a higher amount that % cost of Payment provider fee would be less - but then you started deducting it per sale and so it didn't matter whether you requested a payment on a large or small amount - you'd be losing that % regardless.
PayPal isn't going to charge you $2.92 or even $2.76 to pay me $8.48 I therefore assume there is a fee built into that.
In fact they charge 4 - 6% depending on the value of the transaction. On a 10 euro payment I received from a client the PayPal fee was 0.74 Euro. This is ad-hoc single business transactions. Once you're doing bulk payments that fee is dramatically reduced.