Guys the whole problem with this relates to a concept called Stolen Valour.
That is when someone who is not in the military goes out an buys a uniform on eBay, and they get a bunch of medals and etc. then they go hang out at Applebees and get all the free appies they can suck down, they rent cars and ask for discounts, and so on.
So first they're passing themselves off as soldiers for personal gain; and second they're pulling slimy shit under the guise of being a member of the Airborne Regiment (for example). This isn't a 3 strikes game; it's one wrong move and you're out.
So now you say "well I sure don't plan to do that" but unfortunately this is a book by the cover situation and your intentions can't be judged, just your actions or appearance.
So when you're going to a game and you hop out to gas up your truck in your BDUs with all your ranger tabs and rank badges etc. if you're seen by a soldier from that unit he's going to say what the fuck, and maybe a bit more.
And as a post script for a lot of units when they do go into action their uniforms are pretty sterile.
So if you do it.
Do it right and do it with respect.
Be aware of the unit, their history and what you're wearing means.
Do it on the field. Don't stop for breakfast in your gear, don't post a Facebook profile photo of you in you in a dress uniform. Lerch and ARRSE should be a good enough example of what not to do.
Airsoft, where nothing is hurt but feelings.