[secabeen]

The cost of a nationwide grid is significant. Depending on the terrain and population density, it usually nets out at somewhere between 30%-50% the overall cost of electricity. Sure, if you run a microgrid among a few houses, you won't pay those costs, but someone has to pay the cost to maintain the km of lines to reach deep into the mountains of Bavaria.

Microgrids also have some black swan events that can result in outage; if you are reliant on solar and storage but then experience a 7-day long period of stormy weather and no production. As you note, off-grid is always an option, and when you seriously look into it, you quickly find that costs to have that 24/7/365 service are many times more than just paying to connect to the grid.