What's really frustrating is when a movie uses it in such a way that the plot nearly turns on THAT WORD - and then, when the movie airs on network, something else gets substituted...caught two old-timers on TV just today (still waiting for the leaves to fall to be raked here in S Jersey) in which the N word was used prominently -
Trading Places used it to help motivate Eddie Murphy to do in the Duke Brothers when he was sitting in the bathroom stall and heard one of the Dukes say to his brother "Do you think I'd ever let a N- run our family business?" - of course by the time the movie appeared on the Comedy Channel the word vanished in a blip of silence, as you point out.....
And then there was Blazing Saddles where it kinda disappeared as part of the movie, as in "The new sheriff's a Nig-boing" (bell ringing) - hilarious - I don't remember any great protests about even the potential use of the word when the movie came out, but those were days when everyone wasn't out looking to be offended on any excuse......