How does that help with time? Nearly everyone reading it is most certainly capable of reading far, far faster than listening, no? I suppose if you have an unfortunate, long commute, it might work, but otherwise?
When you're doing physical tasks while not having to co-operate with someone else, you can listen to the audio version while continuing to execute on the physical task.
You can also listen while moving your person about from place to place, which can be quite hard or inefficient to do while reading.
I certainly spend a lot of time moving from one place to another. I also assume there are plenty of people who do the same.
It's quite hard to read while making lunch, cleaning, running, cycling etc. It's also quite hard to concentrate on anything cerebral after a day of work, doing any number of these things and tending to the needs of small kids.
Audio books, OTOH, make housework a joy since I can tune out of the horror of cooking and cleaning and concentrate on accumulating knowledge from one source or another.
Also, much more motivation to run since simlarly, I can just observe my pulse meter occasionally and otherwise concentrate on the book.
