The only time the rules generally come to the surface, is when someone does something that breaks the rules -- and then they receive negative sanctions. In general, however, responses only go in that negative direction. In other words, we receive little direct positive response for doing the "right" thing, but people are free to call us out if we do the "wrong" thing.
Take this fine specimen spotted in an Ann Arbor coffee shop yesterday:

Yep, he is flossing his teeth. In public. And the price he had to pay for having the broken the rules was to be heckled, photographed, and blogged about by me. (Great, now I'm the enforcer of all things proper?!?!?)
But what is it that he is really doing wrong? Well, part of the rules are that we are supposed to show up in public ready to play the game. Goffman refers to the combination of "controlled alertness" (behavior) and appropriate appearance as "interaction tonus." It is something that is supposed to be "on" all the time when in public, not something you put on when you get there or, as was the case with the flosser, you drop and readjust and then put back up while you are there.
Fortunately, there are spaces and props in public space that help us to maintain the fiction that our interaction tonus is our "natural" state. If we need to drop it temporarily or adjust it, we can retreat to the bathroom (a semi-public space with its own set of rules that allow for such activity) or hide behind a newspaper.
BTW, and this continues a conversation Steve Krause and I have had, I'm liking the Primo coffee shop in AA (on Liberty and Fifth). They have two walls of windows overlooking the street, it is warm (even if the fireplace is fake), and they serve their coffee in real and big ceramic mugs.
The only part that disappoints me is that they have single-occupancy (one-holers), gender segregated bathrooms. Riddle me that one, batman. I checked them out -- both bathrooms are the same. No gender specific equipment in either one. But labels matter, as evidenced by the man that showed up to use the restroom and found the men's locked. I had just checked the women's, knew it was empty (and the door was even open), and encouraged him to go on in (he had a sense of urgency about him...). He hesitated. I encouraged more. It took a promise that I would stand outside the door to get him in there. Now what was that all about? Was I there to protect him? Nah, there was a lock on the door. Nope, I was his "excuse" -- if he got strange looks coming out (as he might -- he was acting out of role by presenting as a man but coming out of a door marked "women" so others who were sticking to their appropriate roles would be playing by the rules to call him out -- just as I had done with the flosser), I was supposed to explain it away. As in, "it's okay, the other was full so I told him to go in there." And yes, that I am a woman is the largest part of what would have made that possible. If I'm a woman, and I gave him a pass to use the "women's" room, it must be "okay."