Yeah, I did that too
but I found an lcd is helpful where you can't connect to a PC.
Strictly speaking an LCD would only display time, you can't actually set it using it
. For that you need some buttons.
Anyway I thought about adding a display and/or buttons to my controller but ultimately I didn't see the relatively minor value being worth the added complexity. I'm very much a minimalist. You shouldn't have to set the clock very often at all--that's largely the point of the RTC--and tweaking something is a 2 minute job with a laptop.
In some way I intend this to be demo code and to be as easily adaptable as possible to different setups. To that end I don't make any assumptions about what hardware/driver/controller you have beyond there being an Arduino and a DS1307.