Publishers want them and many have tried. It is the other way around, people don't want to make micro payments. Some say they do, but the evidence proves they're wrong.
Edit: Typo
Edit: Typo
As a publisher, I'd want consistent subscription revenue. The goal is to convince users to pay after they hit the paywall several times.
If you are a publisher, something which gains widespread attention might happen in your region, or an article might become viral for other reasons. You know that a lot of people would like to read that article and not become subscribers. So if you can sell access to an article 50 000 times for 1 dollar, that's $50 000 in income you wouldn't otherwise have.
But unfortunately, very few people are willing to pay a dollar or 50c for an article which they are desperate to read.