Libro.fm is the ethical alternative to Audible. While they don't have a permanent "free" model, they offer a code through partner influencers. Their membership is $14.99/mo, but they give you one free credit upon sign-up. You can use that credit on TBATE . The exclusive benefit here is that your purchase supports a local independent bookstore.
You may encounter sites claiming to offer a "TBATE audiobook free exclusive" download. Be cautious of these for several reasons: tbate audiobook free exclusive