The funny thing is that I NEVER asked anyone from my fish account and he now has friends from all over the world, while his name is "My fish Ploup" in French.
About your fake account and its birthday wishes, An experiment could be to put a erroneous birthday date. I guess that day you can get a lot of wishes, even from close friends. We are just lazy I guess.
It was also interesting to see the cognitive dissonance from some posts: "I'm pretty sure it was your birthday next week, but Facebook says its this week, so Happy Birthday".
Birthdays are a thing that are hard to remember. People used to mark them down on a calendar or just wait for the person to remind them. Both of those functions have been replaced with Facebook now.
Wasn't worth keeping it around after that.