The Internet has undercut voice, text, ""online services"" (Compuserve and AOL etc), news, and most recently cable TV. The only way those prices can be lifted off the zero floor again is by a monopoly somehow squeezing out the free alternatives.
The psychological overhead of billing should not be underestimated as a reason against micropayments. Not having to think about your usage is liberating. This is why bundling (e.g. Netflix, Prime) is not going away.
Content creators do sometimes need to be paid somehow to produce content (although lots will do it for free!), and people seem to be slowly converging on Patreon/Kickstarter for this.
Phone companies are doing transactions per second which requires them to replicate a bank. It might be that you can only buy one thing today (calls) prepaid phones are ordinary bank accounts and phone contracts are credit cards. Where do you, as a banker, think this is going to go eventually? To add to this insanity [I added], you have a 0.50 cent per minute help line. You are already using their bank to sell support to your customers. Hundreds of guilders are transferred per person from your accounts to your competitor every month! Compare the service level: If I don't use the phone often enough they steal my money and close my account!
Over the many years that followed I got properly robbed by phone companies multiple times and hear at least 30 crazy stories from people I know. Schemes not even the greediest banker could dream up. They would go to prison fast.
As usual, the incumbents don't care and have ossified structures and a poor understanding of technology. Banks, in particular, care least about the bank accounts - they're almost a loss leader to get people in for the real business, which is loans, especially mortgages.
In the US, you shouldn't ever use this - you should just use a credit card instead.
In the UK everyone uses debit cards, so I'm not sure if this recommendation is still valid. In the US, using a debit card is possibly the only thing you could do that's worse than "bill my mobile carrier."
I've worked for telcos, and postpaid is indeed very much about "buying customers" via deals/sales prediction models and customer retention; they kindof have to do this, else they simply wouldn't exist in the marketplace. But for prepaid, OTOH, I can't see anything wrong with the prices (ok you don't get a sponsored spyware device every other year).