I do this but it poses a problem for, as an example, banking. When they ask you the answer to your security question over the phone and you don't have access to your computer/password manager. Let's say you're one of those weird people without a laptop and your account is frozen while travelling overseas.
Having a cat named 1FD362BW9L6MBOWRD23SEF43 becomes a huge problem...
That's why I like 1Password. It's on my phone, so it's accessible, and I can do "words" instead of "characters".
So, I could very well have my mother's maiden name be "panda porpoise flutist sandpile", but I understand what you're saying. It may not be for everyone, but I work in the security sector and usually over-paranoid is better than ill-prepared.
Having a cat named 1FD362BW9L6MBOWRD23SEF43 becomes a huge problem...