What the author didn't mention explicitly is the obvious sludge techniques used in media subscription models.
(https://www.behavioraleconomics.com/resources/mini-encyclope...)
In case of The Economist, to which I'm subscribed, you have to call them...on a phone...like it's the 80s
The worst offender of the type is scribed.com that has a fake "we're sorry to see you leave" page before you actually hit the final "yes I confirm that I want to unsubscribe" button. This resulted in at least 30 dollars extra that they got from me.