Once you starting looking for orange and blue in movies, trailers, and posters you can't help but notice that it's everywhere.
Color messes with our emotions, looks slightly different to different people (remember that dress?), and can mean quite different things in different cultures. And, as with any visual medium, color is very, very important to film.
Usually, we don't even notice, but sometimes color themes are obvious. The fantastic and pointed color palette in Breaking Bad, for instance, or how in Hero the color scheme totally changes based on who's telling the story. And then there's Oh, Brother Where Art Thou, which threw subtlety right out the window and sepia-toned everything.
Whether we're aware of it or not, a lot of thought goes into color choice in movies and TV, and a lot of work goes into color-correcting the footage in post-production and the most used colors are blue and orange. The blog I found this histogram in doesn't offer a theory as to why, but this video on the subject by The Verge points out that skin tones often fall into the orange range, and blue is the complementary color. Maybe filmmakers are just trying to make their actors stand out.10.3k