johnstacer wrote:How about whether a sister is a young single adult for reporting purposes, or whether she is a very young or very old mother who may need additional support, etc. Also for the same reason an Elder's quorum leader might want to know whether a brother is young enough to help with a member movein or may be old and too feeble to move furniture. Lots of good reasons, and as for birthday, how about when to send a birthday card?
As russelhltn said, the LCR may provide this information for members of the leaders organization. Because the MLS rights are more coarse grained it isn't possible to restrict extra information to just those a leader has responsibility for.
However, if LCR does not provide that information (and I'm not sure what it does provide for quorum and auxiliary leaders) then I would assume legal counsel and the general authorities decided privacy law or policy would not allow such access. In many countries the legal restrictions are more severe than in the US.
I'd also say that age is a poor indicator of whether someone needs extra support or can provide assistance. Hopefully leaders are relying more on personal visits and home and visiting teachers for better feedback on what the needs and abilities of their members are. As for birthday cards, birthday lists (without age) have always been available to those with organization rights in MLS.