Question for Michael

Regarding Michael S.'s response to Rob's post, I don't understand why Michael says it is "irrelvant to the state as to why someone would want to form such an association."  The state is being asked here to provide privileges to these nonmarital friendship relationships, some of which privileges will impose costs on some third parties that deal with this new unit (e.g., employers).  Doesn't that mean the state should have to articulate an interest in promoting such relationships before it provides these privileges?