It does that to allow them to change the payment method. So for example if they use the offline payment method and decide to use PayPal instead they can and this won't do any harm to CBSubs or risk double-payment. There's no parameter to turn this off.
It would be good to have some sort of indicator of this though. Ideally it could show that payment is pending above the button or something of the sort. Have added a feature ticket to review this further.
forge.joomlapolis.com/issues/8568