Why don't they use compilation clips for actors promoting movies?

Talk shows often times have actors on promoting their movies. These actors usually bring along a clip from the movie, usually primarily featuring the guest. These clips are usually pretty terrible.

I assume this is at least partly because any interesting scene the actor is in probably has spoilers that they don’t give away, but this means that the scene that is shown and promoted gives little feel for the movie, or the overall chemistry between actors in it.

I see this as the same problem faced with trailers, in making a movie seem interesting, without actually giving anything away, but could they not apply the same treatment to actor’s promo clips?

It seems it would be easier than making a trailer, it’s not going to be 3 minutes, just 10-30 seconds at most. Show the actor interacting with a few of the main cast, maybe a couple actions or monologues. This would give the viewers a better feel for the movie, and generate more interest. It does not seem like it would cost all that much to edit together something like that.

Not sure why you think that, I have the opposite reaction. A scene is always more compelling than a few random clips.

Could be, but they rarely seem to use compelling scenes. If I later see the movie that has been promo’d, I usually think that the scene I saw on the promo tour was one of the more boring and least informative scenes of the movie.