Whilst true I think this is a grossly disingenuous response.
What do you do if you have a large supply of electricity that you are currently or periodically not using, but want to store it?
Pumped storage hydro is an excellent solution.
What do you do if you have a disparate collection of variable and intermittent supplies of electricity?
You might well see significant levels of this type of sourcing in the future with renewables.
Pumped storage hydro is again one excellent solution.