The same product, via the same wires or pipes: how can it possibly cost different amounts from different companies? It can't. Of course it can't.
Never mind from the same company. The same company! What do you get if you are on the higher tariff? Seriously, what?
If people realised all of this, though, then they might ask why the utilities were delivered by cartels of pretend-competitors, instead of being where they belonged, in public ownership.
And that would never do. Oh, no. That would never do at all.