This is for the protection of both you and your traveler. As soon as you accept a delivery offer, you are obligated to provide a credit card for the total price of your order, including the 7% Grabr service fee, your traveler fee and other applicable fees. Please note that your card is not charged right away, but rather, it is authorized for the total amount.
Your payment is put into Grabr's secure escrow account and only released to the traveler after you confirm delivery. This incentivizes your traveler to purchase and deliver your product as soon as possible.