Since most of us are pretty simple, (...)
Don't agree that we are simple. To consider the creation of a galaxy, which led to organisms eventually leading to us and you now wondering about us all. Nothing about that seems simple to me. One human being hosts more microbiota (beyond 3 trillion) inside his body than known life forms with thought patterns exist. Even in a philosophical manner: Consider your capabilities to question yourself and reality. Those must be the hardest question a living being can ask and search an answer for. We are complex and unique.
why do we live under such a complex system?
Because we are a complex human being with complex desires compared to everything else. Besides, if something is possible to do we will eventually do it. We have the drive to grow in any direction, bad or good. Our system needs to cater to this drive, as well as to our desires. It also needs to protect us from it occasionally. Even if you consider us pretty simple, we all have slightly different needs and desires with the freedom to chase them. Put enough of us together and it'll get more complex eventually.
Is it an inherent property of the system or just a way for the elites to herd the common folk away from their own self-interests?
An inherent property of the system is to help us develop, protect and evolve. May that be by enforced war or peace. You're likely asking not why a human system is like this, but why some elitist individuals seemingly take advantage of it and why we allow it. We all look for direction. Via work, via partnerships, via religion and via the elite or leaders. This gives space for the system to create a stage where these people can strive and where we can follow. It's not just an inherent property of the system, it's the system reflecting an inherent property of us.
What role do you think scarcity and greed play in all this?
A big one. It creates competition and challenges. If everything on planet earth was in abundance, we never had to evolve as much as we have already. It's deeply rooted within us to strive on competitive forces.
In my belief, all these questions point to one general truth: Everything in our society and around it is set up to make us evolve and grow. Nature's scarce resources, individualistic and collective conflicts, us constantly challenging ourselves or society and our free mind constantly questioning reality. The higher your impact is on steering us within this path, the more space you'll find is available for you to 'do whatever you want'. That's the kind of privilege elitists enjoy and the lack of freedom underprivileged people have, we appreciate those who give us direction or inspiration and disregard those who do not seem to matter. I personally believe more in a sharing/participating socio-economic society but have to accept that our current system is what works best for these times.