Which works until everybody is off the grid and then collapses.

Everybody relies on the fact that the grid is ubiquitous. Street lights, traffic lights, water pumps, etc. When the grid isn't ubiquitous, you lose all manner of things we take for granted.

We've seen this before in California. Some suburbs made a point of being in unincorporated land to avoid being associated with LA. Well, they found out really quickly that their infrastructure was horribly expensive when they had to pay for it all themselves.