I have to admit I was one of those who thought "videoadds will never work in video games" When I made this statement I was thinking about a console/PC experience.
Video games market is still an young industry and new Gamplay and Business Models are being created. This brings new consumption tendencies and new individual & social game experiences. This is so exciting! We have so much to learn from our users!!
This is a short article about Monetization. Videoadds seem a good option for certain types of games
http://blogs.unity3d.com/2016/04/06/new-study-reveals-the-future-of-mobile-game-monetization/