[samj]

Facebook lists provide (barely) adequate functionality for users with large and/or complex social networks to constrain sharing but, like Circles, they're a PITA to set up. Fiven most people don't need them it's no surprise they're buried in the UI, particularly given they constrain rather than encourage sharing.

[code_duck]

To 'constrain sharing' is exactly the point. Maybe you don't want your co-workers, in-laws or not so close friends to see personal photos or posts? Myself, I participate in more than one professional and social group of people. Things I share or say to one group are irrelevant, confusing or just noise to people in the other group and vice versa. So, constraining sharing sounds fine.