I'm currently using the payout option, so itch.io is handling the paypal/stripe transactions on my behalf. According to the terms of service, refunds are my responsibility, but the only means I have of providing a refund is through paypal, and if someone doesn't have a paypal account, that's not going to work so well for a Stripe customer.
I noticed a bug in the GitHub database related to the refund policy being updated in the terms of service, but that was back in May. Any updates here?