Do you have a source for that?
I've worked in the industry, and that 250 MW estimate was my extrapolation of DECC figures that were published, but I'm sorry ICBA to dig out the specific report they came from. There's stuff in the public SMETS2 specifications if you want to look, but that's long, technical and dull, and you still need to make assumptions. The actual meter is only about 4 watts (and it is widely assumed that's taken before the meter, though I can't find evidence either way). The home hub and in home display from memory are in the range 10-20W together, and there's some other technical losses on things like the auxiliary load switch. And there's all the energy used by the "Data Communications Company" and their data centre, that'll be a few MW of entirely incremental wasted energy.
The gas meters are battery powered. Which means that every ten years or so they have to be taken out. In theory the battery could be replaced, the meter recalibrated to standard, and refitted. Realistically most will be thrown away.
You're paying for all the energy use, and all the meters, it really doesn't matter whether that's directly in your bill or not.
Biting the hand that feeds IT
