A video game can also make you open to all races. For example, when I was playing a popular role playing game I had people of all races in my party.
Role playing games in my opinion are a form of 'interactive fiction' whose outcome you can somewhat control. In short, they are also a stories.
The mode of storytelling is one of the most effective ways of communicating ideas to our mind, unconsciously, that is. By having meaningful interactions with virtual people of all races, it communicates to our mind that we are open to those type of experiences.
