I think it's been common practice since at least the 70's to shoot alternate versions of explicit or violent scenes if not for tv, then to cope with the wrath of the MPAA. I've seen nude scenes replaced with underwear scenes. It's painfully obvious when profanity is redubbed for tv, especially by someone who sounds nothing like the actor. (Jackie Gleason in the Smokey and the Bandit films being a prime example.) It's also funny when the phrase "Judas Priest!" is uttered plenty and often in the tv version of the Exorcist. Jack Nicholson says "freak" a lot in "The Shining". (The optically added fog over the very naked Room 327 ghost actually makes that scene more spooky.)
NBC once held up the tv premiere of "Battle Beyond the Stars" until they figured out a way to cover up Sybil Danning's ample cleavage. I doubt anybody would bat an eyelash at it now.

It's a shame that Repo Man doesn't have the tv dialog dub as an alternate track on the DVD. The director once commented he thought it was funnier with expletives replaced by the likes of "Melon Farmer!" and "Flip that!"