Graffiti artists steal the spray paint by shoplifting, and are often hard core drug addicts .. One guy in Wilmington DE was caught red handed (as his hands were covered in red spray paint), and he took cellphone selfies of him and his railcar artwork in the freight yard, when they arrested him, they found his car neqarby, that contained thousands of photos of him, in multiple scrapbooks containing thousands of railcar graffiti ... jail time !