There's probably a good explanation, but let me ask the question: why do we need to have men cutting hard road surfaces?

If a city extends their subway network, they dont demolish all buildings on top, lay the tracks, and then rebuild. They do it without any major interference to the surface. Similarly for mountain tunnels, you dont start by demolishing a mile of rock. We just dig the tunnel.

Couldn't someone invent a robot to dig fibre tunnels? Then we wouldnt need to bother any shop owners or neighbours with noise and inconvenience?