Another benefit of these quizzes is that they can point out potential blind spots. For example, one quiz asks for opinions about punishment for crimes. If I discover I'm an outlier w.r.t. the population, I should reconsider whether my opinions are based on solid evidence (or did I see one study that found tit-for-tat punishment effective in a certain context, and take that as gospel?).

It'd be interesting to have a quizz that also includes questions on what you think other people think - i.e. how well do you know which of your views differ from those of others?