E.L.F.S. Leader: We're your worst nightmare. Elves with attitude.
Charlie: Whoa, how did you do that? How did that feel, Dad?
Scott Calvin: It felt like "America's Most Wanted."
Charlie: Dad?
Scott Calvin: What is it, Charlie?
Charlie: Maybe you better leave some milk and cookies out, just in case. Okay?
Scott Calvin: Great. I'll just go pre-heat the oven.
Charlie: And don't forget the fire extinguisher.
Scott Calvin: Good night, Charlie.
Charlie: My dad is Santa Claus.
Bernard: Excuse me. Are we on a coffee break?
Kid Elf: We don't drink coffee.
Bernard: Then I guess THE break is over! Back to work. Thanks.
Scott Calvin: Here we are. Denny's. Always open.
Charlie: I don't wanna eat here.
Scott Calvin: What are you talking about? Everybody likes Denny's, it's an American institution.
Scott Calvin: Hey, Charlie, you know how to call 911?
Charlie: Sure, 9-1-1.
Answer: The elf on top probably ignored him as he was in no position to answer him. The elves seem to have a stratified society [i.e. some make toys, Judy provides food/beverage, some do security etc.] so it was most likely his job just to punch in the code so the sleigh would descend. With Bernard being the head elf, and probably the most knowledgeable on all things Santa related, he would be in the best position to talk to Scott and answer all of his questions.
Invader_Gir