Homage. They explicitly said it is homage and they are doing a full series of posters paying homage to other 80s horror/sci-fi films.
http://www.slashfilm.com/stranger-things-posters-throwback-thursday/
Homage, come on.
The kids also dress up as Ghostbusters for Halloween. Homage.
The entire show is a throw back to early Amblin and Spielbergian filmmaking.