I've been aware of Banksy's work for many years. But my grand goal with Zombie Pumpkins is to be able to say that all the stencils here are my own design. Even if based on a photo, I stylize it to my artistic tastes, hopefully creating a distinct visual style that might make someone say, "Hey, that looks like Ryan's work."
Sure, lots of Banksy's stencil type art is almost ready-made for pumpkin carving. But since I'm not the original artist, I'd feel bad translating it too directly for my pumpkin pattern collection. I prefer to choose imagery that I can reinterpret enough to really make it my own.