We split the service costs and insurance fees over both renters and owners because both benefit from the services of SnappCar and its insurance partners. For example, a renter benefits from being able to make a payment, and an owner benefits from receiving the payment, so both should pay a part of the cost.
Similarly, the renter benefits from having an insurance during the rental, while the owner benefits from having his or her car covered during the rental, so both should pay their part of the insurance fees.