So if someone "notices" something printing, that MIGHT be a firearm, and confronts that person about whether that's a firearm or not, what are some of the responses from members going to be?
1. Oh, I didn't tell you, must be none of your friggin business"?
2. I'm presently on a bag until they can reconnect my arse
3. firearm? Gun? oh hell no, I voted for Hillary
4. ignore the question and continue to your box, get your mail and leave
You see, if it's concealed and prints where a cleark may ask if that's a gun/firearm, that clerk can not detain you in any way. You are free to leave. Worst case scenario, the clerk gets your plate, brings an inspector into the matter and that inspector then makes contact with you outside the PO later. That inspector can/may question you, but he has to have evidence of your actually carrying in the PO, not just a suspicion to have any teeth whatsoever.
Or another possibility, he calls the locals. You're gone, they get an apb out for your vehicle as the clerk took your plate. You're now in public domain. Leo's ask you if you're carrying, yes. Were you carrying in the PO? No. They also need hard evidence you were carrying in the PO, not just suspicion based on some clerk "thinking" it might have been a firearm.
What's all the damned fuss about? They check the video tape, yup, that sure looks like a gun printing. Well, I don't care what it looks like, prove it was a firearm is where there's any teeth to the matter. Now, do I want the hassle of any of the above? Of course not, but I'm not going to worry very much about it either.