That policy exists because of EU and US data protection laws for children under the age of 13. Facebook cannot legally allow them on their website without significantly changing the way their data is handled and requiring parental consent.
Facebook most likely doesn't mind the current state of affairs where preteens lie about their age (hook 'em early), but they do not officially condone it.
Facebook most likely doesn't mind the current state of affairs where preteens lie about their age (hook 'em early), but they do not officially condone it.