One of my great-great grandfather's worked as a coalminer in Pennsylvania in the 1860's. His father died and he left home at 12, because his step-mother had young children and he had to support himself. He was from a large Mennonite family in Pennsylvania. He went to Nebraska in the middle 1870's and homesteaded, lived in a sod house on the prairie near Lincoln.
Life was just plain hard for most people in the world in the 19th century before the fossil fuel age. And it may become hard for us again, but I think its important for people to remember our roots.
EROEI isn't nearly as important as ROI. As long as people can scratch out a living mining coal, its going to be mined, just as oil production is going to continue as long as people think they can make a living at it.

Bob Ebersole

ROI is subordinate to EROEI for primary energy sources. There is no economic value in digging coal, or oil, or Uranium if you cannot get net positive energy from it. That only works for things like batteries where people will pay a premium for the energy in a convenient form.

We never thought much about ROI in energy planning. As Schumacher put it there are two basic commodities - fuel and food. All others are secondary. For fuel and food, short term market prices are a poor guide for long term planning. Overriding importance is attached to secuity of supply.