This statement is exactly correct with the exception of “trial period”. Costco does not grant a trial period but rather a six month return policy.
Returning a hearing aid just to “flip” to a newer model is financially damaging to both the merchant (Costco) and to the manufacturer, and these costs are passed to other consumers.
The merchant loses the credit card fee on both the sale(s) and the refund, as well as their time to sell and fit the hearing aid(s).
The manufacturer loses out on the used returned aids which can no longer be sold as new and are often discarded.
Finally, there are reports that Costco will block future sales of hearing aids to members after a certain number of returns, although I have yet to see confirmed information on the exact number of returns or dollar amounts.