The benefit is that troops that you know are going to die, don't have to die in such huge quantities. Many times you send out a suicide squad that has no chance, but you need it to draw fire. If this would be of no benefit to you, then you would never use it. If it is, then you would.
How would it hurt you to have this implemented? Why vote no and block something that others want? I don't get it. I can see not having an opinion and not caring, but I don't see voting against it. So what am I missing?