you have protection against shady merchants by initiating chargebacks.
The opposite is true also. As a former affiliate I experienced things like 3 month chargebacks (and even heard of 5 month charged back) or that customers charging back immediately after they got refunded. As far as I know the CC companies allow only a 1.5% chargeback rate or hefty fines apply. Not to mention that the CC system is insecure by design and it is the merchant who has to take the risk.