Trivia: Most of the names on the check-out card in the book are actual fictional characters or real people, most being pirates. There's Davey Jones, Bluebeard, Blackbeard, Captain Kidd, and Frank Beard. Frank Beard is a member of ZZ Top and incidentally the only member without a beard. (00:03:35)
Trivia: The two surfer dudes eating Krabby Patties after Spongebob and his friends appear, are Lloyd Ahlquist and Peter Shukoff, the creators of the internet series "Epic Rap Battles of History." They were also the writers and performers of the rap battle before the credits.
Trivia: The two popsicle sisters holding hands are a reference to "The Shining"
Trivia: The baby in the stroller that said "SpongeBob" is voiced by Stephen Hillenburg, the creator of SpongeBob.
Answer: The point of a trailer for a movie is to get bums on seats in cinemas so the film-makers have to make a film look really good and generate a "I really have to see this" vibe. Because virtually all professional films shoot far more material than they need, some of it will end up in the trailer as exclusive content and some will end up in the special features section of the DVD (bloopers, deleted scenes etc).
Neil Jones