On the local level, writers communicate through tagging or piecing. When someone begins writing they soon become aware of all the graffiti they never noticed. The more tags, the more fame and the more attention - that's the game. Graffiti can quickly become an addiction. Writers see walls or billboards and imagine their work sprayed upon it.
Most writers paint for more than fame.
In painting there is release or a sense of accomplishment that contradicts the destruction of other people's property. For the serious writers, there is a loose code of ethics involved in writing. There's a complex distinction between the immoral and the destructive. Painting on someone's house or car is looked down upon. But painting on billboards advertising Camel Cigarettes is seen something wonderful.