Being Devil's Advocate, is it not the case that it is not the job, right or even requirement of an aerodrome authority to seek out miscreants to it's airspace!?
We had a helicopter land in the LCTR between Waltham and Ascot once... primary only with no clearance. I had a heliopter on freq and he said it flew fairly close beneath him (not bad as my helicopter was on "a not above 1000ft" clearance!)
Anyway - I just reported the facts..... Should I have made sure the infringer didn't depart the next day? (as it did - ironically, I asked a transit if there was a heli on the ground and he said no)
As an aside, I know James and Tudor professionally and socially, and find them both thoroughly good chaps. (along with many other fine people contributing here)
Nothing is as black and white as it seems.
As for the security issue: No amount of line drawing on the quarter mil will actually stop an infringer..... but it does mean that there are extra sensitivities involved.