Legally, in terms of sentencing/fines, it does matter if he hurt someone. It makes a difference if he used the uniform to defraud anyone financially, which could include accessing discounts offered specifically to veterans, etc, or if he passed himself off as an officer to gain employment for a position he was not qualified to do, etc.
If it is discovered that he did not use the uniform for monetary gain, etc, whilst the offence he has caused to those who legitimately served will be considered as a victim impact, his crime will be limited to a breach of the uniform act which will be a fine at most.
If he has been using the uniform in, say, a romance scam, that will be a second offence pertaining to the scam itself, not the uniform if wore to augment it. If he has been involved in financial fraud, that's a different charge again.