From a reader:

I am not an engineer, so this probably makes little sense, given the last post.
However, many folks of all ilks would likely flock to Generator Spas looking to burn excess calories (energy) with an eye toward being green and lean. Criminals (low grade) would do the same, given the alternative of putting an orange vest and picking up litter. Many folks, currently using no energy, but having it, might want to come in and make a few extra greenbacks to buy beer.
This isn’t an energy in, energy out argument. It is about turning unused energy into usable energy.
Engineers will clean my clock on this response.