The reason why it is not done is because it would lay bare all the inequities in the system, as well as require higher taxes due to not being able to hide the inequities in various forms of price discrimination/segmentation.
Keeping prices obfuscated means costs can be distributed across the population in an unfair manner / benefits reaped in an unfair manner, as well as ability to punt costs into the future.
Is that a common justification for UBI? I have not heard it but it would be a big reasons for me to support it - any reading you know of?
Tax deductions, credits, student loans, subsidized mortgages, taxpayer funded pensions, Medicaid reimbursing differently (lower) than Medicare reimbursing differently than Tricare, and so on and so forth.
It is always a political decision to reduce total costs, or drive the benefit to certain populations, or use liberal assumptions to present future costs as less than they really are and so on and so forth.
If we want people to have a house, give them money to buy a house. Or a house. Same with education, healthcare, everything. The big problem with this is cash has to be accounted for today, transparently, and cleanly. There is no option to muddy the waters.
Openness is a great default, and while I will say a lot of things are more complicated than I know, this will at least drive the discussion into the open.
IIRR Fannie Mae originally had explicit anti-Black lending policies. I do wonder how that would have been dealt with in a more open environment.
The fact is, the utility does not know how much money you cost them in a given month and it's impossible to say. Some of your electricity is being generated from a plant planned and built 40+ years ago, long since paid for. Is that electricity sold at the cost of fuel and maintenance? Electricity generated from a new plant then has a corresponding capital cost component but how's it portioned out at the customer level? What if they had to go change your transformer 20 years ago but your neighbor's still on their old 50-year-old transformer next door?
Unworkable.
There are generators independent from utilities, yet they figured the pricing out somehow.