Most deaf people don't want the implant, so I guess they assume their deaf children would feel the same way. I took a sign language class and I learned that many CODA people often wish that they were in fact deaf. I found that hard to believe but I was looking at it from my perspective (as someone who has been able to hear since birth). So I asked my grandmother who is a CODA (child of deaf adult) as well as her younger brother, both are hearing, and they both said that they often wished that they were deaf, while their deaf siblings said they rarely wished that they could hear. Neither my grandmother or great uncle could really explain why they felt that way. So I'm guessing that perhaps, when both of your parents are deaf that's the world your raised in. Your parents probably have deaf friends who also have deaf children and even though you have no problem communicating with deaf people because the deaf world is all you know, you may still feel like an outcast. Coming from the hearing world we see it as a disadvantage and pity them, but they for the most part just see it as who they are. Just my own personal observation, most of my maternal family are congenitally deaf.
And can't these children always get a cochlear implant if they are a candidate for it later on? I mean maybe if they're going to have a microphone sticking out of their head they might want to make that judgment call.