Jack,
That sounds like an easy question to answer and in some cases it is. Every rally is different depending on the person putting the rally on. Some are just that meeting great people making lifelong friends, exploring an area that you have not been to before, some have speakers, tech issues, games, movies, boat rides, golf outings, dinner shows, but it has been my experience that one of the requirements is a potluck dinner, however not mandatory. Remember when you attend a rally you already have several things in common with every other attendee there, you all have a Heartland product and you like camping.
Like I said every rally is different whether it is a Chapter, Regional, or National, When you attend a rally you will find that every Heartlander is friendly, helpful and ready to share experiences with you.
dave