How did you go from £40 per customer to "billions"? How many households do you think there are in the UK?
Even if each of us lived alone it'd add up to £268M, an order of magnitude lower than the lowest reasonable definition of "billions".
I hate to interrupt someone when they're ranting, but if your anger is based on bad maths then it might be worth thinking again.
268÷40 = 6.7mm implied population. You probably meant 2.68 billion and 67 million implied population. Makes the last sentence above humorous.
Google says a 2.4 individuals per household in the UK, then add small commercial properties and individuals with more than one on property meter and I'd be surprised if the total meter count is much less than 50 million. 2 billion total pounds, but further adjustment to remove people who took smart meters voluntarily.