Well, they are regulated medical devices, so that hinders disruption a bit. But they're pricey and probably not quite worth all that's paid for them. But, whe

Well, they are regulated medical devices, so that hinders disruption a bit. But they're pricey and probably not quite worth all that's paid for them. But, when you need them you need them and the DSP's needed to do some of the noise reduction (and their size) prevents a trivial alternative. Unless you figure that the brains will be in a watch or smartphone... But they have to sound pretty good, which makes for expensive small speakers. High-end earphones, I think, are at least as pricey as the mid-grade hearing aids in that both have to be sonically clean at worst.