I really hate camp sites. Normally because we use lightweight technical equipment that we take up mountains. The ground may be flat in a campsite with few stones, but it's normally rock hard and difficult to drive the pegs into. What I particularly hate about camp sites are that other people are there and I don't have privacy to go to the toilet in the middle of the night if I need to. Also that we've normally always gone to a camp site because we can't afford a B&B or hotel. We#ve tried taking cheaper campsite equipment that's bigger and more spacious, but it all takes up more room in the car and therefore more hassle to find everything that we need.
Wild camping on the other hand is a beautiful experience. I know that we have the whole mountain to ourselves. We may not get a good night sleep but if we've been doing lots of climbing whilst carrying loads of camping equipment them we're normally quite tired when we do try to sleep. It's also nice to hear wild animals outside, or even to see them. I'll never forget the wild horses we saw by the side of a loch one night. I'll never forget the midges either but that's another story. Stuart once woke up one morning and opened the tent to find himself face to face with a stag! Or another night when an owl was flying around a few few feet above our heads while we were building the tent.
I've never actually been wild camping for more than one night in a row though. I always wanted to do a multi-day low level wild camp and hike in Scotland. Maybe even combine it with kayaking.