I didn't know about furries until after I graduated high school in 2010. I also then found out one of my best friends from there was a fox furry, but he had no idea what a fursona was or Fur Affinity. There's also another girl from my school who isn't a fur, but seems interested in them, plus her uncle is a dragon fur, FA porn artist and former fursuiter.
So, only one fur I know IRL, and he doesn't really seem to know much about it or anything anyway.