That’s not quite accurate. There was a trend for a certain period of the 70s (and early 80s) for ‘Fotonovels’ - books retelling films via a series of stills. These were achieved via photographically enlarging actual film frames (probably an interneg?) and gave a visual summation of the film in the days before home video.
Many were small paperbacks, though some were larger format books - I have Psycho and (probably the best example made) Alien. The Star Warses never received this treatment, for some reason, but I imagine it was discussed.