Ratings systems like the ESRB or the MPAA may be useful tools for helping parents to decide which movies and video games to buy, but the fact that these guidelines are rarely heeded by parents suggests that these ratings systems need to help parents better understand what they do.
Media producers advertise in publications for adolescents, screen trailers for restricted movies on TV at times when kids are likely to be watching, and recruit teens and children (sometimes as young as seven) to evaluate story concepts, commercials, trailers and rough cuts—even for R-rated movies. Film and videogame industries also target children as young as four with toy tie-ins for adult-rated movies and games. Therefore, even if a specific movie is unsuitable for children to watch, toys, t-shirts, and other merchandising tie-ins are not considered unsuitable to purchase.
The marketing of adult entertainment to children has been, and continues to be, an ongoing issue between government regulators and various media industries. In a report released in 2000, the U.S. Federal Trade Commission (FTC) took movie, music and video games industries to task for routinely marketing violent entertainment to young children. Subsequent reports since then have shown that although advances have been made – particularly within the video game industry – there are still many outstanding concerns relating to the frequency that adult-oriented entertainment is marketed to children and the ease with which many under-age youth are able to access adult-rated games, movies and music.  Specific areas where the FTC is calling on entertainment media to improve on include: restricting the marketing of mature-rated products to children; clearly and prominently disclosing rating information; and restricting children’s access to mature-rated products at retail. 
As for the music industry, all five major record labels continue to advertise albums with explicit or violent content on television programs and in magazines that have substantial followings of children and youth under the age of 17.
Despite this, there is little evidence that violence in media actually appeals to children, even young and teenage boys.  Instead, what appeals to them is characters who take action and solve problems; whether this is done through violent or non-violent means makes little or no difference to young viewers. 
 Federal Trade Commission (2009). FTC Renews Call to Entertainment Industry to Curb Marketing of Violent Entertainment to Children. http://www.narm.com/PDF/FTCReport_1209.pdf
 Andrew Weaver, Jakob Jensen, Nicole Martins, Ryan Hurley, Barbara Wilson. “Liking Violence and Action: An Examination of Gender Differences in Children’s Processing of Animated Content.” Media Psychology, 2011; 14 (1): 49 DOI: 10.1080/15213269.2010.547829
[iv] Götz, Maya. “Girls and Boys on Television.” International Central Institute for Youth and Educational Television (IZI), 2008.