Why does Lobo have a 'beeep'? I have the profanity filter off? Besides, if something needs to be censored it was never intended for the audience at hand. It's either a game suitable for children, or it isn't. He uses other exclamations like 'frag!' but it was deemed necessary to have the profanity then censor it?
Comic books censor cursing all the time. It is called "grawlix." This is a comic book game. It's perfectly in character and the devs likely did it as just a fun little thing because, as you likely know, Lobo has a foul mouth in the comics.