Squadgy - I just rang my friend who was also there on Saturday just to be sure that I was not wrong and he also confirmed that the public announcer stated (roughly from memory, but in essence correct):
'We get quite annoyed with this ladies & gentlemen and these Pilots should know better, there is a no fly zone here up to 2000' and we will be reporting these Pilots to the CAA. We have good binoculars to get their reg.'
Now I remember seeing the notice at Barton but because I was not flying on that day I didn't look any further into it. Lets just say it was a friendly 'note' from a well meaning Club Member - how can a public announcer come out with something like that to literally hundreds of people?? It must be wrong, surely?