I think the pop-eyed goldfish are pretty hideous, personally. I also think the ones with huge bulging bellies, or weird jelly cheeks, are horrifying. They do, however, have their fans...which makes them a successful animal, in evolutionary terms, because they're propagated and cared for. Do they suffer? Probably not usually, though I'm sure they're more prone to certain accidents.

As for scaleless snakes....they don't appear to come to any harm, either. They have been found as wild adults, too. In captivity, it's just not an issue for them, so we may as well enjoy the wonder of the oddity that nature has created.

It's difficult for me to imagine an alteration to the form of a snake that would cause it distress, but would still be a viable animal. Remember, ball pythons just don't cope well with being uncomfortable. They aren't like mammals, or like fish.

But again, where is the logic in complaining about today's morphs, just because of something that might happen down the road? Talking people out of breeding spiders now won't change that.
You will have to wait until that happens, and complain about it then, because doing so now has no effect.