You only have to look through sites like !!!!!!!!!!!!!! to realise that photography airside at UK airports is widespread, most reasonable people would consider this to be harmless(including myself), however different airports appear more tolerant than others.
I have legitimate reasons to carry a camera airside and I do occasionally take airside photos, but I only do so for my own use. I dont post the images anywhere and if i did so I would probably use an alias. I think where the main problem arises is when anything that is commercialy or security sensitive is photographed and then published, so the easiest way to control it, is to stop it happening. I could make a tidy income from selling images from my access but I dont want to compromise my position. So I hope that things stay the way they are and paranoia does not set in everywhere.