You are implying that a child's need for security in the form of having stable caretaker figures, guaranteed not to disappear no matter what happens, is a learned cultural thing. While this is in theory possible, every intuition I have gained from my exposure to developmental psychology disagrees, and quite strongly so. E.g. attachment theory - yes, there may be several attachment figures, but that doesn't mean that being betrayed by any in the form of abandonment is going to be any less shocking. You also haven't addressed the feeling that ensues from the thought that you can never really rely on anyone, knowing that anybody could at any time choose to abandon you, and the effect that is going to have for forming commitments later on in life. Or the constant pressure to be "good enough" not to be abandoned that children in such a scheme would constantly be exposed to. Young children are distressed by even such minor things such as disruptions in their evening routines, to say nothing about the knowledge that your entire home might change at any moment.