Well, if they draw something and declare "That's my friend Foo!". If you show up with a stuffed version of their drawing, they are likely to recognize that as "Foo". Kids have a way of not letting their lack of drawing skill or details get in the way of a good story.

Plus, I doubt they could turn a 3 year old's drawings into something. My kid's drawings aren't that recognizable yet... (just lines and squiggles)