worked at windells for 5 years. each session has on average 10 to 20 adult campers (ages 18+). you stay in a separate house just across the street from campus. in addition to being able to take part in all of the regular camp activities the adult campers have a separate agenda with their own activities which include dinners our in the surrounding area, trips to portland, private after hours time in BOB, etc. from my experience it seems the adult campers have the most fun. you have the option to stick to a schedule and do the activities or you can just make up your own plan and go your own way, you are an adult after all. This freedom or structure appeals to a lot i think. Think of it like an all inclusive vacation. also the adult campers get to know the staff and visiting pros on a more friendly level than the campers sometimes do because they are generally the same age and hang out after hours.
so in summary i would suggest going for it. you get to do all the fun stuff you did as a kid and have zero responsibility. and if you want to be an adult and do grown up stuff, you can also do that.