The whole theory that selfish material interest and selfish pleasure seeking is ( or should be) the main driving force behind economics and society rules is what make the world in bad situation today.
This is the essence of living, conscious beings.
Consciousness defining pleasure and suffering, and life defining offspring preference, the obvious behaviour of any conscious, living being is what you just stated.
The negation of this is what I call the social lie.
It's one of the composent, but far to account of all aspect of human psychology. Aka plato myth of caverne or body as tomb of the soul.
Reward based system is Pavlovian. It's good to train dogs and breed kapos in nazi camps.
If that's your view of human psychology, and expect everyone to act upon such theory of mind ill let you at it

I guess it become the norm now.
But if the network is entierely built upon selfish interest, you cant complain in the same breath that miner act selfish and steal your money because it's profitable to them, or miner empty block for the same raeson. Perfectly acceptable behavior then. Nothing more to expect from any conscious being.
And I still maintain that bitcoin is built upon sociopathic theories.
https://youtu.be/ImbQwCu5GdM 