Something that happened to me recently is kind of relevant here:
Coming back from NAE12 on the train, I was dressed in DPM, wearing my vest because it wouldn't fit in my DPM bergen (with side pouches) with the ammo pouches stuffed with AK mags (because carrying them there made the bergen a little easier on my back) and carrying/wearing my MK6 helmet with cover, skrim, rubber and reflective recognition strap, so, apart from my shoulder length plus hair, I suppose I did look quite militaristic...
A plain clothes detective came and engaged me in conversation. It was pretty surreal because my instinct was to be secretive, but, after I quickly thought it through, I decided just telling her what was what was the way forward. However, she started into her cover waffle, which involved being somewhat flirtatious and using that as a cover for curiosity, which momentarily threw me, as she was quite good looking, and, for a second or two, prompted by wishful thinking I suspect, I began to doubt my assessment of her. The conversation between us flowed on and there just didn't seem to be a right moment to say, "Look officer, I'm just coming home from an airsoft event. I have got two RIF's with me, but they're out of sight in/attached to my bergen and I've also got my Skirmish Airsoft Mansfield membership photo ID right here..."
Then I started to get paranoid about what she might do if she realised that I knew she was Old Bill (and if any of you are wondering how I did know that, it's difficult to explain exactly because it's more than simply a checklist, but when you have been "a person of interest" enough, you do just know {although these days I'm as pure as the driven sh... er, snow}), like maybe her own paranoia would kick in and she'd think my ready answers, ID, etc., were all a carefully planned ruse... So we waffled on for yonks, her doing her shtick and I doing my best to appear as clueless as possible as she "ferreted out" the info I would have been happy to supply anyway lol!
You'd think they'd have better things to do really, wouldn't you? But don't be surprised if you find yourself in a similar situation if you do post pics of yourself holding what could be a real firearm...