There is one very very distinct line with any form of real world identification worn in this hobby:
Role play. People putting on clothing and wearing identifiers to greater immerse themselves and those around them in the simulation.
--- THE LINE ---
Impersonation with intent. Someone who wears a uniform or other credentials, and intentionally misleads people they come into contact with claiming they are something they are not, outside of the scope of the game they are playing.
For example, I played a game at a school recently, we were supposed to be Russian internal affairs agents. We dressed as best we could and had hoaky documents with our names on them. It was a laugh.
Then there are lowlives who show up to milsims in cadpat and rank patches, and while in the safe zone talk to real CF members, and carry on in a manner which would mislead others to believe that they are CF officers. When they are not. This is shitbaggery.
Ár skal rísa, sá er annars vill
fé eða fjör hafa. Sjaldan liggjandi úlfur
lær um getur né sofandi maður sigur.