Movie posters are a complex subject. Way more complex than they have any right to be. Look at the poster for "The Towering Inferno". Steve McQueen's name is le

Movie posters are a complex subject. Way more complex than they have any right to be. Look at the poster for "The Towering Inferno". Steve McQueen's name is left-most while Paul Newman's name is the highest. William Holden is lower than both of them and to the right, lining up with McQueen's last name. And Faye Dunaway is about half an line lower than Holden's last name. Then there's fights about how big someone's name/picture can be in relation to others. Look at the live action Beauty and the Beast Poster. Emma Watson gets a lot of poster estate and first billing. Then it gets a bit crazy. Not to mention, how people are billed is a bit contentious as well. You'll notice that it's mostly a list of names except the final two. "with Ian McKellen and Emma Thompson". That's because being a special mention is worth something. It's a way to give prominence to non-leading actors who are significant in other ways. The Thor movies do this with Anthony Hopkins. Clearly he's not the lead, but dude has had a career and he was a big get for the movies. For Ragnarok, they even toss it to Mark Ruffalo, probably as a way to acknowledge his part's significance in the film. Spider-man: Homecoming is another interesting one to look at as well as it gives a lot of real estate to Robert Downey Jr. Tom Holland has a smaller picture than the Spider-man suit, while Robert Downey Jr. is much larger than the Iron Man suit. Michael Keaton also gets the double up, but both of his images are much smaller. A lot of the Marvel posters are good to look at to see the politicking that goes on as they do a lot of ensemble movies. And then there's also the fact that sometimes the pictures are made before the credits are put on it. So you're locked in an image but contracts dictate name order.