I wanted to add..... while yes, I think it's absurd.... I'm also well aware that this could well be a regional thing or even something town or camp specific. For all I know, the OP has kids at a camp that's done things this way for 4 generations.
That's why I reiterate.....ask some of the other parents what they believe is a customary "rule of thumb" (Don't ask specifically what they do). And when all else fails, call the director's office and make an inquiry. You won't be the first to call.