The price of a high-quality hearing aid can discourage a lot of people since many of the prescription hearing aids can cost several thousand dollars. This price is quite high, especially when considering that most options contain components that are found on every laptop or smartphone, so the question of why it costs so much appears.
The answer is quite simple once you consider the size of the device. A good hearing aid needs to miniaturize many components and that can be expensive. You also have to consider the amounts of money that each manufacturer invests in the research and development of products.