For someone with an oxygen machine, yes it is. Many of those billions just don't have the option for this, they would end up committed to a hospital or dying because the treatment would never be seen as viable.

And now that I say it: hospitals need electricians too. Electricity goes out in a hospital for too long, lots of people die.

And actually a third point: electricity -going out- is not the only thing that could kill a client, it's not too hard to start a fire.