I think it's probably just a common thought process. I'll pick an animal -> dragons are the coolest animal -> nobody will ever guess dragon, this is way better than using my dog's name.
Have you ever seen those online riddle things that say pick a color, pick a tool, wow I bet you picked a red hammer! We all grow in relatively similar societies, we all have relatively similar ways of thinking.
> I'll pick an animal -> dragons are the coolest animal -> nobody will ever guess dragon, this is way better than using my dog's name.
I must confess, this is typically my exact thought process when crafting a password, a username, or even sometimes a nickname for people to call me in real life.
