Well, maybe some do, but that's a preference thing.
It's easy to forget that editors are not superhuman when they hold the power to make or break careers in the palm of their hands. But editors have tough jobs. The truth is, many of them are overworked.
Imagine going to work every day and having that stack on your desk grow by hundreds of submittals. Daily! And truth be told, many of the submittals are really not very good. But wading through and replying to the masses is not the only thing editors do.
After finding a manuscript they like, they sometimes have to fight for it. There are acquisition meetings where an editor has to say why they want to buy a manuscript. If there are others like it in the house, or in the works, the editor might be told "no". Imagine how heartbreaking that is, finally finding a story she wants, but still can't buy it.
Let's say the editor gets the green light. Then the negotiating with the author begins. That part can be stressful and exciting. If all works out and a contract is signed, the editor may provide suggestions on how the author can improve the manuscript and work with the author to get the story "just right".Schedules and deadlines are set.
Then the marketing stuff commences. The editor works with the author to create wonderful blurbs and cover information. Quotes are requested. Dedication and reader pages are made. The editor may consult with the author about creating websites. Blog interviews may be scheduled.
The editor then works with the author to fill out art form pages, the information the art department needs to create a beautiful cover for the book. The editor may attend cover art meetings on the author's behalf. The editor does her best to make sure the author's story is accurately conveyed in an eye-catching cover.
The editor sends the manuscript to a line editor for such things as grammar and word choice fixes. Once the manuscript has been edited and signed off, the book is well on it's way.
It's amazing that editors do this work day-in-day-out for many, many books. It's a seemingly impossible feat.
So, maybe they do wear capes and tights.