That something occurs locally, doesn't mean that it is efficient to govern it locally.
Just because something occurs, that doesn't mean it needs to be governed at all. For the most part, people can live their own lives without a government mommy watching and second guessing everything they do.
And are you really trying to claim our huge central government is "efficient"? It must be really, really efficient for all that efficiency to outweigh the corruption.
Good luck running an economy with people that have diplomas like 'Smartest kid in the world. Signed, mom' or getting trains to run on railways with different widths.
Economies aren't "run". Individuals make individual choices.
Standardization regularly happens without government edict. The government didn't write the standard for email, for example, but there's still a more-or-less universal standard. It was all done without threats, without police, without graft, without government hearings, without bailouts for the losing technologies, and without paying an email tax.
...died and their empire crumbled. Their centralized government didn't save them.
Also, you should appreciate what centralized government has already done for you personally instead of taking it for granted.
I do appreciate what they do. It's just not worth the cost. I appreciate a good hamburger. I don't want to pay $2000 for a good hamburger. I don't appreciate being policed and regulated and threatened and spied on and otherwise oppressed in return for the opportunity to get on a waiting list buy a good hamburger for $2000.