An Unacceptable Question

Reproduced below are the introductory paragraph and one of the bullet items from Harvard's "Guide to Unacceptable Interview Questions." (See this FAS web page for top level link.) Why would information that may not be asked of a faculty candidate be dispositive of a student's eligibility for team captaincies, Rhodes nominations, and leadership of student organizations? That's not a rhetorical question. Why is asking about a candidate's club memberships prohibited? Perhaps it is Harvard policy not to discriminate against candidates on the basis of organizations they join--in which case our motion does nothing more than afford students the same protection. Or Harvard is bound by some Massachusetts or federal law which codifies the same principle. If anyone knows the rationale for the prohibition, please do share. In any case, this does seem to bear on the hypothetical I posed to the Faculty Council, about how the faculty might feel if the policy applied to them.