I think it kind of depends on where you camp. For the most part most people do not touch other people's things but you always get the goofballs who mess things up.
I find, though, when we are at the house trailer campground, we don't have a problem. But I think it is because it is a small neighborhood and people watch out for each other's property.
When we are tent camping, I try to put the "valuable" things out of sight in the car or somewhere someone would have to work to get at.
When I first saw the quesiton, I thought you meant security like people coming into the tent or trailer at night. I worry about that when I have the grandchildren with us.