and where do get your fact??? Concealed means not visible, I have carried concealed at many events, even in those places with the “gun free zones” signs
In Mass you needs specific license to carry concealed. He did not have that license.
He would not have made it through the security check point without setting off the metal detector.
He must have had a holster in his waistband or under his shoulder. It was clearly visible.
BTW, I'm glad you have not been caught.