I have been a member/participant in larger theme camps several times, and have served as the organizer of smaller theme camps (15-30 members) eight times. I have also had many discussions with other camp organizers over the years. Here are a few things I have learned.
There are as many ways to organize a theme camp as there are ideas for theme camps. Having said that, it is much easier to organize a smaller camp. Big camps are a lot of work, and it is typical for organizers of big camps to participate in little outside of their camp. For some people, organizing and managing a camp is great fun, and Burning Man benefits greatly from their work. However, many people that initially offer to help organize a camp get bogged down when faced with this large and complex task, and may drop the ball. Primary organizers will find that many of their willing "helpers" will actually do much less than you would like. That does not have to be big problem, but just like planning for bad weather, camp organizers need to anticipate flaky camp mates. So, unless your have camped with them before and seen them do a lot of heavy lifting, don't put big expectations on new camp members. When making plans with new camp mates, it is a good idea to step down your expectations.
Camp dynamics are particularly important to me, and I would rather pick a congenial group first, and then figure out a theme and interactive events for the camp. With flexible people, it is not that hard to get agreement on cooperative events. With this in mind, we don't invite people to camp with us that we do not know well.
In our camps, we have usually had an organizer that took care of communications with prospective members, applications, postings of events for the program, collecting camp dues, and figuring out how to arrange the camp (where each person/group will be located); and an art director to lead creative activities (camp decoration, costume themes for our parades, nature of performance art, and so on). This division of leadership has worked well for us. It is the art director that organizes the camp planning meetings, and the work parties for camp decorations and art.
Camp dues - Most, but not all, theme camps require membership dues ranging from $20 up to $500 or more per person. We use camp dues for purchase of swag imprinted with our camp logo, bar supplies, and special pieces of equipment (lighting gear, extension cords). We ask that all camp members commit to being in the camp by paying their dues a month in advance, and we don't let them camp with us if they don't pay in advance.
In a small camp, it is easier to manage group meals. We ask that everyone be self-reliant for their food and sleeping shelter, and the camp organizer arranges for a communal shade structure, shower, and evaporation pond. We organize group meals on an ad hoc basis. That is, some days we have group meals for the whole camp with each individual providing something, and on other days we eat independently. This works for us, and works better when the camp has 15 members than when we have 30.
Clean-up - It is essential that several of your most reliable camp mates stay to the end and make sure that you leave no trace.