I'm not sure what's creepier - the privacy issues, or the fact that everyone seems to be assuming that machines can make better fashion choices than people.
Is it that hard to imagine that a machine can do a better job than at least some people, particularly if the machine is trained by experts and/or Big Data and/or even Mechanical Turk? There's a reason we have terms like "fashion-challenged" after all.
Also, even if its judgement were about as good as a person's, it might be helpful in being able to quickly render that judgement vs. people to-ing-and-fro-ing. A machine might be able to even provide explanations for why it thinks something looks better than others, e.g. "While this outfit fits you well, it does not look as good on you now as it did 5 months ago -- its light colors make you look very pale, possibly because it is currently winter and you are not as tanned as you were then (or perhaps you just have a cold) -- better to save it for summer months".
Also, even if its judgement were about as good as a person's, it might be helpful in being able to quickly render that judgement vs. people to-ing-and-fro-ing. A machine might be able to even provide explanations for why it thinks something looks better than others, e.g. "While this outfit fits you well, it does not look as good on you now as it did 5 months ago -- its light colors make you look very pale, possibly because it is currently winter and you are not as tanned as you were then (or perhaps you just have a cold) -- better to save it for summer months".