From the producers of… What is the purpose of advertising the producers of a film in terms of marketing?

[PragmaticDramatic]

I understand why advertising the director makes sense but the producers?

If they’re mentioning a successful or popular film that you enjoyed it may lead you to try the one being advertised as well. The producers have a significant influence in how a film turns out, so if you enjoyed one film they’ve done then you may like their other work too.