Free Caricaturist

Surely everyone must have seen them. I know I have.
The caricaturists at zoos.
I want to be one.
For free.
Sure, it might take a couple years of learning to draw caricature art, practicing, and getting fast enough to do it on a time crunch with impatient people, but I think it'd be fun! Just picture it. A nice, relaxing day off. What better way to spend it than at a bustling zoo making peoples' days with fun portraits?! 
I asked a classmate if she had ever considered being a free caricaturist. She said no. 
Surely I musn't be the only one.