Utilitarianism vs Libertarianism question - thought provoking As libertarians want to minimize state intervention, it would be consistent with their position, and if permitting this would maximize happiness and well-being it would be consistent with utilitarianism.
The libertarian could argue that as it's a voluntary interaction, the state should not interfere with people's free choices. This could be on the basis that choice is in itself valuable, or that choice leads to something that is valuable, eg. happiness/well-being.
The utilitarian could argue that the result leads to less people being brought into existence, and that the happiness/well-being experience by the female drug addicts receiving the $300 would pale in comparison to the happiness/well-being that would otherwise be experienced by the unborn. Alternatively they could argue that were the female drug addicts to reproduce, the potential persons would have such a poor quality of life, that it would maximize happiness/well-being the most by permitting the female drug addicts to receive the $300 and guaranteeing that the potential persons do not come into existence.