Because there are many children that could view their content and corrupt their lives. There are many of the clubs near where I live surrounding my elementary and high school. I live in a lower middle to a low class neighborhood and the adult content located within reach of a child or posted on walls where you get your hair cut was common. You have to be a certain age before you can enter a adult video store or strip club, there should be laws that prohibit adult content by being viewed by a minor at every place. For example, you wouldn't want adult content posted inside the walls of a McDonalds. Yet some places would allow it. Some places have nude beaches and nude colonies. I'm not sure if they should be banned. Some places the other extreme is observed - women are not allowed to show any part of their bodies in public. In a perfect world, children would be free of Pornography and Adult content. Yet it is human nature to have attraction for the opposite sex.