I don’t know what your evidence for those stories are (cone planting and totty hunters), but I have heard them too. It would not surprise me if they are true. But are they really flying dangerously (or for that matter illegally)? A twin engined police/coastguard/navy helicopter is very different from a small SE fixed wing.
Cause I used to know people in the Coastguard and the Navy
And no, I don't think they were flying dangerously either.
EA