Booster you are correct I was initially quoting Effy.
But my point is the same. You/We are not going to retrain/educate people one camp site at a time. There have always been and will always be dishonest people.
It's nice to think we don't need prisons. But bad guys exist.
We have fire stations and ambulances, as much as we don't like it fires and accidents are going to happen. Human beings have flaws and will always exhibit some bad behaviors. That is not going to change whether we like it or not.
The neighbor campers are not hardened criminals but they are opportunist and scavengers on the lookout for items they can claim as their own.
We must use rationale precaution to avoid our items being taken.
Leaving them unattended is simply not working for the OP. Scolding each offender on CG at a time is an effort in futility.
This is the definition of insanity.
Repeating the same behavior over and over while expecting a different result each time. Keep leaving the stuff out and neighbor campers will keep taking it.
Car theft is illegal. Nevertheless I would not suggest you leave the keys in your car with the door unlocked when you are out and about.
Same principle applies to camping gear. We are not saying it's OK to steal, but I am saying putting things away in the first place will resolve the issue.
After years of camping, the reasonable conclusion is you can make the effort to put things away before you depart. Or you can spend the time finding and retrieving the items when you return.....I'm out!