Based on your question, we can see that you care about your online banking security and we want you to know that RCU does too. Our new multi-factor authentication solution requires something you know and something you have. Your password is the something you know. Your device with the cookie is the something you have. We do this for your security. A web browser cannot get your MAC address to positively identify your device to the detail that we can by using the cookie method. You will continue to need a one-time passcode at every login, if you clear your cookies, as this ensures security.
I'd like to offer another possible solution for you. For your other internet browsing needs, it appears that you have another reason for wanting to clear your cache and cookies, so you may want to keep a browser that you use only for online banking. Then you would not need to clear your cache and cookies so often. With your main internet browser (pick one: Internet Explorer, Chrome, Firefox), you can continue to clear your cookies regularly. With your online banking internet browser (pick a different one: Internet Explorer, Chrome, Firefox), you would not clear your cookies regularly. Then when you use Royal Credit Union online banking with your online banking Internet browser, you would not need a one-time passcode at each login and it would remember your device.