This scene shows sacrifice because the townspeople are sacrificing Tessie Hutchinson just so they can keep their tradition. The story says, "Alright, folks,' Mr. Summers said, 'Lets finish quickly." The townspeople do not really want to stone Tessie to death, hence why Mr. Summers says he wants to get it done quickly. The village still does it anyways because they are so blinded by tradition that they are willing to sacrifice Tessie.
Tessie being late to the Lottery foreshadows her not being part of future events because at the end of the story she is the one killed. In the short story, Mr Summers says, "Thought we were going to have to get on without you, Tessie." This line foreshadows that in the future the town is going to have to get on without Tessie because she is the one that dies in the end.
Shirley Jackson creates a serious and anxious mood at this point in the story by having all the characters stand in a line with very serious faces. The story says, "soft laughter ran through the crowd as the people stirred back into position after Mrs. Hutchinson's arrival." The crowd was all standing in "position" with little laughter because they were nervously awaiting the lottery. Shirley Jackson used the characters to create the mood of the story.