I wish someone would make a netflix for audiobooks. I'm guessing licensing is an issue.
Talk to your local library about whether they're on Overdrive / Libby. If so, you can listen to unlimited audiobooks, ebooks, magazines, and comic books 24/7. It's fantastic. It's free. Yay public libraries.
Additionally, there is a plugin for Firefox called "Available Reads" that allows you to enter your Overdrive account information for your various library cards. Then, when browsing goodreads, the plugin will show you the Overdrive availability of the books you are browsing at all of the libraries at which you are a member, and provide links out to the catalog entry for those libraries' copies of the ebooks/e-audiobooks.
ACX/Audible pays 40% for exclusive royalties. So your $30 audiobook will get you $12 in royalties. Amazon makes $3 from your subscription or $18 if someone buys it straight up.
Even at a 25% royalty structure you're still looking at $7.50/audiobook which doesn't work well with an all you can listen/netflix style program as 2-3 books puts the store in the red. Some companies will offer 'all you can listen' but will cut you off if you listen too much.
To get it to work publishers would need to agree to a flat fee for unlimited listens for a period of time. Which doesn't seem likely at this point.