Give me one example where somebody would wear an unearned medal that was not intended to benefit them...even if it was simply for self-aggrandizement, or because the pretty colors matched their clothes and eyes, it's (at least in their mind) advantageous to wear it.
They are using the medals as jewelry then to create a false impression. From a moral standpoint, this is deception to the onlooker, since each medal means something.
What these braggarts want is attention, and the remedy is to ignore them totally or call them on their elaborate lies in front of everybody (public humiliation). Once found out they usually slink away.