Because people (with money to spend on journalism) want a way to pay for just the articles they like.
Note that these microtransactions are where you pay a small amount of money for a small amoint of content. They aren't the burger joint model of MMO DLC where you get the buns as part of the original game, with cheese, burger, salad and condiments as microtransaction downloads.
Because people consume a lot of little things. Ads are essentially involuntary micro-payments. It's a way of aligning the interests of content-creators and with their users rather than their sponsors. What's wrong with micro-payments?
Nothing inherently, its just that they are generally used to extract more revenue from the existing model instead of supplant existing incomes.
There have been several studies about decision making being taxing the brain, and always being presented with a dollar sign for any part of your experience can be a bit wearing.
If your domicile had the ability to charge every time you go to the restroom, I guarantee they would just raise the rates until you considered pooping your pants.
> they are generally used to extract more revenue from the existing model instead of supplant existing incomes
Blendle is doing the latter and I would only argue for micro-payments in this context.
> If your domicile had the ability to charge every time you go to the restroom, I guarantee they would just raise the rates
Going to the bathroom is something you need to do, not something you choose to do, and the friction of finding another bathroom every time you want to is quite high. Reading articles is by no means a need and free alternatives are a button tap away. You're comparing one of the most demand inelastic services with an incredibly elastic one. They will never be able to extract unfair prices because readers will simply stop reading.
So I agree that micro-payments have their place, and that place is the digital world where we consume many small things that we could do without if we thought that they were too expensive. The world that most of HN lives and breathes. But to write off micro-payments entirely is short-sighted.
As for your original question, the reason a lot of people think that micro-payments are something that people want is probably because of Jaron Lanier's book, Who Owns the Future. It's a good read.