I use this to allow different levels of access in my Siege house.
My own and my husband's room doors are 'co owner' access. The guests we have staying with us have 'friend's' access, and a couple of people I sometimes make things for are simply 'accessed'. I have a box in the house set 'secure, anyone' but of course the only 'anyones' who can reach it are those that are accessed to the house.
tbh I trust the 'accessed' people enough to friend them, but since it's not just my stuff that's at risk, but that of the people friended, I don't do that.
We have 5 'guest rooms' for people from Europa who stay with us sometimes if they're just trying out Siege, or if they want to keep their Europa home and play Siege too. The doors of those rooms are set 'friends'.
Accessed people can wander round the main part of the house, but can't enter any of the bedrooms