My wife got caught in a mobile ad game. After a thousand of them she finally said, "I'm bored why not" and got addicted for a few weeks.
When I saw the ad of the game she was playing, I was mocking her like, "Oh is that in the game?" And she showed me. Yeah, it totally is. Usually as a special event, or some "mini game" inside the game.
Well damn guess I was wrong.