"This essay, which I am about to record as an audiobook […], and will thereafter upload to ACX as a self-published, free audiobook." Doctorow seems to have int

"This essay, which I am about to record as an audiobook […], and will thereafter upload to ACX as a self-published, free audiobook." Doctorow seems to have intended to release this audiobook on Audible for free. However, when I look it up on Audible's website, it is on sale for a regular price of £3.69 (or £3.23 / one credit for Audible members). I wonder why this is. This is not a criticism of Doctorow; I think he probably doesn't expect people to actually pay for it, and he's released a DRM-free copy, free of charge. I wonder if this is something that Audible enforces (i.e. they do not normally allow audiobooks to be available free of charge). I have seen some audiobooks available free of charge on Audible, but perhaps those are the exception rather than the rule.