Refunds are sent back via the original payment method. Affilliate payouts are sent via the client's choice: Paypal, or credit applied to their hosting account.
Refunds are sent back the way they came and any other payouts are usually paypal, cheque or what ever the customer wants if I don't have to go too far out of my way. That was when I was in hosting. I am not any more so my answers relate to what I have done in the past.
paypal, MB, Alertpay. Alertpay is best, i have to say. If dispute arises in Paypal, then seller should IMMEDIATELY refund the money without having to wait for the verdict. That much BRILLIANT is their dispute system ..lol