I think you're mixing two interesting concepts here.
To be honest, everything ever conceived by men at any time is pretty much a conception of men and nothing else. For some reason we seem to give special meaning to certain actions and beliefs, leading to the creation of gods, nationalism, romance value, need of supremacy, and everything else ever accepted by "the tribe". However, for that very reason, I think it's stupid to care of anything of that at all. Why would valuing a god or a nation be better than valuing plastic? They're both ultimately stupid. And here, my friend, is why it is important: It keeps us away from chaos. You've said it yourself; we do certain actions to be part of the tribe, accepted, and thus protected. Anybody who isn't part of us is to not be trusted. If you're not from us, you're an stranger. In the past this may have led to physical conflict, but nowadays it only isolates the stranger away, or he just gets abused by the tribe's member to show off.
Now, what happens when you are the stranger? How likely are you to survive/not be chased away?
The trick, my friend, is to learn how to build masks. Lying should become your first weapon, and manipulation your objective. People are manipulated by plastic, use that to your favor. You're alive already, and you may as well make things better for you. People with power manipulate others all the time, even nations, and nobody complains. Nothing is important and there is no meaning in anything at all, for that very reason you are free to choose whatever you want, because your existence is as empty of meaning as every single other one. Don't fight against the current, just get out of the water and walk upstreamward. The less junk you carry in your luggage, the faster you will go. And masks, my friend, are not heavy at all.