There is the potential for a problem with airport security, but in my view if someone could get through by simply wearing a pilot's uniform then the security operators deserve to be hung out to dry.
Years ago when I worked for an airline, one of my jobs was issuance of ID tickets, and a man wearing a pilot's uniform came in asking for a ticket and was referred to me. Naturally I asked him for his airline ID card, this before I even became suspicious, at which he got very belligerent and asked me if I thought he'd be wearing a pilot's uniform if he wasn't one. Instead of getting drawn into an argument, I stood my ground and told him I needed his ID card. He said he'd go back to his hotel and fetch it and I suspected that would be the last we'd see of him.
He came back half an hour later with one of those crappy little business cards you print on a machine at railway stations! It had spelling mistakes such as 'Captian' and it said 'Elal Israeli Airline'. I just laughed him out of the office.
As it happened he was a well known Cape Town con-man, an Israeli who lived off con tricks.
As is often the case, he got his just deserts a few years later when my young female assistant came to work very distressed having had a collision with another vehicle on a roundabout. The other party had been driving a battered old car and there was very little damage to it but he'd been very unpleasant and abusive and when he submitted the quote it was for significant damage to a Mercedes. We went to the police who knew the man .......... it was of course the same chap ....... 'persuaded' him to drop the matter. Sadly he got a couple of bruises in the process of being persuaded!