What about cases where 2 pieces of clothing when bundled together have value due to making it more efficient for people to find the right size, but over the right size is found the other becomes waste? A company can't prevent a consumer from ruining the wasted clothes.
But that is how physical stores currently work, where you can try the stuff on, before you buy it? If you care about this, you can of course take the upper one to try on, like all do and then buy the lowest one. But you wash the clothing anyways before actually wearing them, so it doesn't really matter. Honestly I don't get your point.