Quote Originally Posted by Tipi Walter View Post
But you bring up an important point of Camping Spots and the First Dibs Rule---whether you have a fire or not. And this applies to both regular backpacking trips to wilderness areas or to the AT. Some CSs are large and anyone can come in and camp nearby---you don't have First Dibs. But for most tent sites the First Dibs Rule applies---i.e. I was here first so don't horn in on me and move on to the next CS you can find. It's common decency and a respect for privacy in the backcountry.
I suspect that many would not know that is a rule, simply due to their being many places where it isn't. As you mentioned, most any spot along the AT that is designated site doesn't work that way (see any site during the time that the main flow of thru hikers are going). Also, other areas that suggest the opposite (like many marked sites here in NY, that have a capacity, and are supposed to be shared until said capacity is reached, as that is preferrable to having many small sites pop up in a given area).
Not that it is the best thing to do in all spots (like your example), but without knowing the people in question and what they have experienced on other camping trips, it is hard to know what they are expecting when coming to a site.