You could be right.
I read a few more articles on this.
The shooter had one gun in each pocket. A .32 and a .22 cal starter pistol. They are roughly the same size which may have lead to the confusion.
He did bring the gun to the lodge on occasion for a legitimate purpose, taking deposits to the bank.
It wouldn't surprise me if alcohol also played a part.
Like you said, even prop guns must treated with respect. Remember Brandon Lee?
(Funny, the older I get - 70 just doesn't seem that old any more.)