Teal and Orange: why?

Supported by nothing but my own observations, I'd say the short answer is trends. With or without marketing research, films have always followed stylistic trends in much the same manner as have fashions and hairstyles, automotive design, architecture, music and so forth.

Tinting and irising of the 'teens and '20s gave way to elaborate optical scene transitions and fast-paced montages of the '30s; sedate fades and dissolves prevalent through the '50s were supplanted by direct cuts, jump cuts and non-linear editing influenced by the French New Wave in the '60s; the polished studio look of previous decades, photographed with sumptuous lighting and elegant tracking, dollying and crane shots lost favor to gritty location work, zoom lenses and hand-held cameras in the '70s; orchestral scores fell by the wayside to pop song soundtracks and music-video-style cutting in the MTV age; the '90s shaky-cam fad became passé with the advent of CG-aided swirling, swooping and soaring 21st-century cinematography dominant in action films, but eventually seeping into depictions of even the most commonplace activities like phone calls or walking from one room to another.

These are all broad generalizations, to each of which there are numerous exceptions, but the stylistic cinematic signatures observable in most films readily identify the eras in which they were made, every bit as much as giveaways like makeup and hair or autos and telephones.