I can't believe this feature was not part of version 1.0. Also can't believe you have to ask why. Here's what I'd like it for. I want to water zones 1 and 5 for five minutes every fifteen minutes starting at 3am, five times. Watering this way reduces run-off on my sloping yards. To set this up without having a copy feature will require creating five new schedules completely from scratch. With a copy feature I would only need to fully specify one schedule, then copy it, rename it, and change the start time four times.
BTW, in my Chrome and IE browsers the part of the interface where you specify which zones you would like to water in this new schedule doesn't work. All zones are checked by default and the interface doesn't recognize when I click to uncheck. I had to use the phone app to create my new schedules. This software is tedious and buggy.