Even if a movie is ultra-violent, it can’t afford to get an NC-17 rating. “An R rating means a child cannot be admitted to a movie without an adult or guardian. An NC-17 rating means no children are admitted. With such a rating, most mainstream newspapers will not run ads. But more important, video stores like Blockbuster will not offer the DVD’s on store shelves. And mass-market retail chains like Walmart, where studios can earn as much as 50 percent of a movie’s revenue, will not sell them, either.”