I don't see why your groupmates couldn't benefit from it. I mean, it is a campsite.
Camp
It could be a roll-away campbed, and if that was the case, you'd have to be getting pretty cosy with your groupmates for you all to benefit. I don't see it being a camp with a fire, burning stove and tents type of affair, due to the fact that you can camoflauge whilst being camped and an actual camp would hardly sit nicely behind the bushes. To camp, could mean that instead of just sleeping anywhere, you are preparing a little spot with putting some nice soft shrubbery down to rest on, or whatever.
Plus, it would be like a lullaby-type affair, because Camp has certain sleep requirements, which result in penalties if you don't meet them. Imagine taking a nap then your ranger friend camps, meaning you can't awake for x hours until camp has wore off. Could get pretty annoying.
Dey
Especially if you can't camo, like the ranger can.
I know... >:-)