Game design has an impact on health and well-being. Due to their evolving capacities, young people and children are especially sensitive to the negative and positive impacts of media design choices. To protect vulnerable people, ethical and responsible game design practices are necessary. But what constitutes “ethical” and responsible game design? Defining “behavioral design” as video game design decisions that elicit, either accidentally or purposefully, self-negative or self-beneficial behavior in the gamer, we draw from expertise in public health, game design, and legal scholarship to analyze current game design practices. Our work illustrates the centrality of changing business models with game design and the resulting tension within games. In practice, monetization strategies regularly guide decision-making in game design, facilitating risks for gamer welfare and finances.