I once had a couple of spotters turn up at our field and ask to be allowed to look around. I politely explained that it wasn't possible that weekend, since there was an air-scout camp going on that weekend (which I was helping run) and for care-and-control reasons we were, for that weekend only, restricting access to the airfield to known club members, the Scouts and their leaders.
A week or so later, a somewhat biased view of what seemed at the time to me a perfectly polite encounter appeared on a spotters bulletin board slating our place as probably the most unfriendly airfield in England.
The result, totally unintentionally, has been virtually no spotters ever since
; although as I explained at the time, they'd have been perfectly welcome the following weekend, I can't honestly say it's done us any harm.
G