As mentioned on the other thread, the most recent film I've walked out on was the utterly vile, Wolf of Wall Street. Can't remember what one before that was, but it was well over ten years earlier.
I can't understand anyone refusing adamant to ever walk out, it's an admission either that they have no judgement or that they don't trust their own judgement. If you don't like a film it is fine to stop watching it. No one has an issue with stoping watching a movie at home (do they??), so what's the difference with somewhere where you have paid money? Ditto with music and books. If you're not enjoying it, or getting anything out of it, stop.
Unless you're a masochist, of course.