What's vital in any payment system is that the people paying the price get to negotiate the price. There are lots of places
where phone companies act as your billing entity. It used to be common for your long distance company to bill you through your local phone bill (especially after the break-up, to simulate what people had before.) The local companies got greedy and charged too much so many LD companies do their own billing, even though credit card companies charge plenty.

What you really want is a simpler, cheaper 900 service with efficient billing. One where you can charge 2 cents/minute and not have the telco take too much of it. But it would still involve telling the caller the price if it's above a threshold they set.

The issue here is not the value of telco billing. It's that the price is set by regulators, hidden from the user and billed to the carrier who can't negotiate it up or down. Real markets and innovation require either true flat rates (like the internet) or a means to negotiate.