I find the early morning child wake up call is a trade off for those that stay up all night chatting and giggling.
If you want silence, you should go to a campsite that doesn't allow children. I know Fforest Fields has a quiet area which is a good idea.
I find that if you tire them out in the day and let them go to bed a bit later they sleep later. DS is a normal 7-7'er and stays up until about 8:30, combined with all the running around, sleeps until about 8am.
I agree it is a trade off, my dp is a late night chatterer which means he cannot and does not complain when we get up early and make noise.
I usally take comics for ds to read in a morning when we go camping - the novelty of them keeps him entertained a good half hour as he doesn't get them at home. We then have some cereal and I take ds and a cuppa for a walk.