I can see paying for the mold if you get a custom mold made. However, you cannot compare hearing aids to a car, computer, stereo, TV, or other commodity. And for that matter … yes, I bought a Sony TV and decided I wanted a bigger one. The store gladly took it back and allowed me to just pay the difference for the larger model Sony. I also bought a home theater receiver and did not like the sound and returned it for a full refund. In both cases there was no restocking fee either, and the return was based on the simple fact that the item did not perform as expected. Hearing aids are much more individualized though. There is no telling whether one or another will work with your loss, or what it will sound like. I do not expect to pay thousands of dollars for something that is so iffy and then be stuck with it.
As for the audi’s time, the audi I went to is a licensed audiologist, not just a dispenser, and her policy is a 60 day trial period at no expense and extended to 90 days if you work with her to try to resolve any issues … full refund if not satisfied. Indeed, in the State of California, by law, you have 60 days to trial hearing aids with a full money back return if not satisfied. And yes, my audi informed me of this fact and said if I went elsewhere to ensure they followed that rule as well. And when I first went to her for a hearing test and to inquire about new aids, she offered to just clean and adjust my old aids at no cost for the entire session. I was also a first time customer there, my previous aids were bought across town, and I did not keep that a secret. She impressed me enough to keep me as a client.