Clothes that were originally in the game.
Mafia II - pohyby - Sector.sk
Another evidence that Vegas DLC clothes were originally in the game but later removed to be sold as an additional contest.
Mafia II - characters (CZ)
As you can see there were many types of clothes to wear. Even Joe was designed to wear much more apparel then we can see on him in the game. Another evidence can be seen at 5:11 where Vito wears the apparel that was added later in Vegas DLC Pack as an additional clothing.