The film that Samantha watches on TV whilst babysitting is George A. Romero's Night of the Living Dead (1968), a film in the public domain so the filmmakers didn't have to pay rights to use it.
Shot on 16mm film (very popular in the '80s) to give it a retro stylistic look.
Promotionally released on VHS in a clamshell box. The last major motion picture released in that format was A History of Violence (2005).
Shot over a period of only 18 days.
Deliberately shot in the same kind of style and using similar techniques as the splatter films of the '70s and the '80s which it emulates.