A good analogy is buying a car. If I buy a car and make a video at the beach that happens to include the car, what right does the car manufacturer have to say, "The video incorporates my IP, so therefore we're going to force you to show ads for our car"?
You could argue that videogames are somehow different. But they're not. If someone makes a video about having fun with their friends, then the game they're doing it in is almost incidental. For example: http://www.youtube.com/watch?v=uD5J5LEBVCk
Videos such as that one take a lot of work to make. It takes many hours to record the content, many hours to edit it, and a way to promote it once it's made. The game maker probably doesn't deserve any slice of revenue generated from that. The game is incidental.
You could argue that videogames are somehow different. But they're not. If someone makes a video about having fun with their friends, then the game they're doing it in is almost incidental. For example: http://www.youtube.com/watch?v=uD5J5LEBVCk
Videos such as that one take a lot of work to make. It takes many hours to record the content, many hours to edit it, and a way to promote it once it's made. The game maker probably doesn't deserve any slice of revenue generated from that. The game is incidental.