I don't know if you ever worked with tech-illiterate people, but there is no way that they would print out or write down a list of codes or keep something in cold storage. Hell, even if they know how to. It's too much effort for something like email, and yet they wouldn't realize the importance until it's too late. I personally had to deal with an aging woman who had her online banking password set to her name followed by the year she was born in, and was unwilling to use the USB security key that the bank started providing. There was more than a million in her account. She couldn't be fucked to secure that kind of money with a free-of-charge easy to use key. It was not a case of an elderly woman struggling to remember her password or not understanding how to use it. In her mind she deserved the access to her account just on the merit of it being "hers", and she saw the security as an unnecessary ritual that the bank used as a barrier between her and her money and nothing could convince her otherwise.