I was in DUB recently (last Tuesday in fact) and was asked - very politely - by an ICTS chap not to take photos "in this area"; I took that to mean the gate area being used by the DL 777. What a time to tell me to stop - not that this stopped me of course; I just went around the corner.
Aer Rianta, in their limitless wisdom, seem to have struck up a relationship with this company and given my dealings with them at LGW (similar to Locohaul's at MAN), it doesn't bode well.
The worst aspect is not so much the inconvenience it causes to people taking photos, but the concern that people are not thinking. The battle against terrorism is as much an intellectual one as as it one of putting into place new security procedures. When you get morons making up rules as they go along, it does raise the fear that you're getting a less bright kind of person doing security. Was ICTS chosen because they did a better job, or because they were cheaper? I suspect the latter. You can't have security which is not focused on the actual threats and this is what is happening here.