I recently wrote a short article regarding Film Sanitization, the practice of removing objectionable content from a movie without the copyright owner’s consent. Groups remove the sex, violence, nudity, language, drug use, etc., to create versions suitable for “families and children.” This raises various copyright issues, discussed in my article, which you can download and read here. The initial conclusion is that those who sanitize films without the copyright owner’s consent do so at their own risk.
Similar issues could very well arise with respect to video games, except that it’s harder to remove just the objectionable content from a video game without the help and assistance of the game’s developer, as evidenced by the “Hot Coffee” exploit for Grand Theft Auto: San Andreas. In any event, some issues to ponder, and you might just find the attached article an interesting, if brief, read.