Basically, a peep, no peep or kisser button all do the same thing which is to force you to anchor correctly (the same) each time you draw.

If you have good repeatable form and a perfect anchor every time, you don't need any of those things.

Trad shooters will often use a finger in the corner of their mouth or some such thing, just like a kisser button. But they don't use pins either. And most of them limit their shots on game to under 20 yards.

It's things like peep sights and fiber optics that have brought archery to the mainstream. For 99.9% of us, that's a good thing.