Chargebacks are inadvisable in case there is digital content associated with the account. In every terms of service I've ever read there is a clause saying the consumer cannot perform chargebacks. They're likely to nuke your account for "fraud" if the bank reverses the transaction, potentially causing thousands of dollars in losses.
Says all purchases are final. You may only request a refund and they reserve the right to deny it. Forcing it via chargebacks basically locks your account.