I personally saw cases in the Army where guys would show up in my unit wearing badges and tabs they never earned or went to school for and got caught. Despicable.
What few ribbons and such I ever had I had actually been awarded. I would have never done anything like that.
In the 11th ACR back in the early 70s we got a new Corporal assigned to our Troop. He was a picture perfect looking soldier but had a nasty habit of putting his nose in Sergeants' business. He undertook to marry the daughter of the Regimental Sergeant Major which was his undoing. Corporal F. had a pay problem - was being paid as a PVT E2. The Sergeant Major, fixing the problem for his soon to be son in law, discovered that Corporal F. was in fact PV2 F. and had forged his orders. Appropriate action was taken. Yes, there is a God.