I personally don't care if a guy dresses as a service member. If the guy wants to be a jack ass and impersonate a soldier, let him make a fool out of himself. Stolen valor guy never know Army regulation and easily make mistakes that gives them away. For example; flag on right shoulder, name tapes and us army tape on wrong sides, and fat bodies with ranger tabs, and SF tabs.
I'll go as far as to call them out to their face, but I'm not going to make a scene and record it. I feel like that's a cry for attention from both parties. Just correct the issue, tell him how much of a fool he's making himself out to be, and carry on.
That's just me, though. I'm just a "don't give a fuck" kind of guy.