Stepping back away from the line of a good putt is only one of several body habits common among golfers. In the case of backing away, I suspect it's derived from the professionals acknowledgement of the crowd after a made putt. Golfers I think don't want to walk down the line of their putts. You can also see golfers holding their finish position for a long time as long as a travelling putt looks like it has a chance to go in. This actually has a biomechanical basis in integrating the good putt with the feel of the recent stroke.
Another habit is the club twirl after a particularly good feeling swing. I never saw anyone do this before Tiger Woods, but now it's a common sight. No one twirls their club after a poor swing. But if someone does the characteristic stiff-arm-club-twirl-walk-after-the-shot routine, you can be sure it's going to be a good one.
How about the habit of not looking at the ball after a good tee shot? If a player studies the ball flight closely, it's probably flirting with trouble. But if he immediately reaches down for his tee, it's right down the middle. On the other hand, a good approach iron will elicit full admiration from a player, as though to get all the good feelings out of a good swing. Why the difference?
Another give away is to look immediately at the ground after a poor swing. As if to blame something on the ground for your poor swing mechanics. Again, it's a unique golf-ism.
Body english and talking to your ball are other well known golf-specific mannerisms. As if you could telepathically influence the balls flight by twisting and turning your body or telling your ball to "hurry" or "sit" is going to do anything.
I'm sure there are others but I'll end with a story from my playing days. One of our foursome hit a short wedge thin into a tucked pin and immediately started yelling at the ball to "sit! sit! sit!". Just by coincidence there happened to be a stray dog trotting along nearby. The dog immediately sat down and looked at the guy doing the yelling. We were rolling on the ground laughing, and we still get a chuckle from that decades later!