Other mistake: Max says that Michael is the "Man of the house" and won't come in until he's invited, which Michael sarcastically does, except Michael isn't the man of the house - its actually his grandfather who owns it.
The Lost Boys (1987)
1 other mistake
Directed by: Joel Schumacher
Starring: Kiefer Sutherland, Dianne Wiest, Jason Patric, Corey Feldman, Alex Winter, Barnard Hughes, Corey Haim, Diane Wiest
Continuity mistake: Near the middle of the film we see that Michael has a transparent reflection in a mirror because he is a half vampire. Yet, earlier in the film when the other vampires, who are full vampires, are in the video store, their reflections can be clearly seen in a glass counter. (00:12:10)
David: Drink some of this, Michael. Be one of us.
Trivia: The boardwalk scenes were filmed on location at the Santa Cruz Beach Boardwalk in Santa Cruz, California.
More questions & answers from The Lost Boys
Answer: Because the Head vampire, Max, had fallen in love with Michael's mom. At the end of the movie he said, "Boys need a mother and if I could get Michael and Sam into the family, you would have no choice but to join us."