Usually when fish are born with deformaties, that is it, like humans and animals, its not going to have issues later down the line, its hereditary. Yes as people say they dont understand why you buy it, i dont agree with this, can you imagine a breeder or importer sifting singularly through small fish to see if there all in tact, myself ive brought fish from a shop, got home then realised ive had one with one eye, to be honest at the time it was my preference fish, little bit of a charecter, does not effect them and they adapt very well,just think blind cave fish have adapted since they lost the use of there eyes,much like humans do, they could have lost the eye after birth and its healed over, With humans these things happen, my little sister had a stoke at 21, she has lost three quaters of her eye site, im not going to put her down because of this,
Thank you those are my views too.