So audio has been my form of book reading on commutes and while cycling for some time.
In Denver there are shelves and shelves of audiobooks in the main library. Lots of cassettes left and a universe full of CDs. Even the branch locations had 150 to 200 square feet of full audio shelves. Now I live in "progressive" Portland and the Multnomah County Main Library has one gondola dedicated to audio and the Sci-fi section... Don't blink or you'll miss it. It tales up about .5 to 1.5 linear feet on 5 shelves. It shares the shelves with Westerns and there is a gap between them.
and the Sci-fi is mixed in with Fantasy. I do understand that to a lot of book "experts" insist that riding around on unicorns and waving magic wants is EXACTLY the same as faring open space in a spaceship even if the physics are a logical extrapolation from current theory. I like both but I tend to draw a distinction between fae magic and space ships (which exist in the real world) and energy weapons (which also exist in the real world).* Ok, some of you will argue that Fae magic does too exist in the real world but It does not get on well with iron. There, another distinction :P
Oh, and if you like series books don't expect to find the first of the series. Go ahead. Search the catalog. See what I mean?
*I confess enjoying Warlock in spite of Himself, A delightful mix of cold iron Sci-fi and Fae magic in the same story.