I'm not sure why you think so, it's pretty standard to pay according to what you consume when supply (capacity) is limited.
I agree that for consumables it makes sense. I pay x dollars a gallon for water and n dollars per kilowatt hour of electricity at home. I would agree that "pay for what you consume" makes sense for broadband, both mobile and at home, if the charges themselves actually made sense. Even $0.05 per text is absurd, considering each message is a low-bandwidth near-tweet using a (formerly or mostly) empty emergency channel. The "true" cost per tweet is negligible. Similarly with broadband, the "true" cost of a gigabyte is in the noise and is somewhat lost in the cost of hardware, facilities, cooling, staff, line crews, etc... (All things *any* service provider has in their costs, like utility companies).
The reason we end up paying for what we consume with utilities is because the cost of production, transport, and waste is measurable. We can measure cost per gallon of water. We can measure kilowatt hour generation, storage, and delivery to a house. How do we measure something that we can make an infinite number of copies of, if the cost to make a copy is near zero?
It is much easier to suggest solutions when you know nothing about the problem.