yeah this bugs me too. its ok if done in moderation and is appropriate. however i find games like COD, GTA ,extra. to overuse these words to sell games.
GTA doesn't use profanity to sell, it uses it because it's appropiate. You're controlling a low life criminal who goes around stealing and killing for money, did you expect him to speak ye olde english? Also, it has gratuituos violence, sexual content, and more gratuituos violence. Believe me, it doesn't need the foul language to sell.