IAPP Exam CIPT Topic 5 Question 77 Discussion

An organization is launching a new online subscription-based publication. As the service is not aimed at children, users are asked for their date of birth as part of the of the sign-up process. The privacy technologist suggests it may be more appropriate ask if an individual is over 18 rather than requiring they provide a date of birth. What kind of threat is the privacy technologist concerned about?