To me, the author uses the normalcy of life in The Lottery to convey the horrific meaning of tradition done for tradition sake.

The description of the day (it's nice outside), the smiles and laughter of the men talking (it gets a little uncomfortable), the reaction of Bill Hutchison (going through with this without emotion or nervousness like Tessie), the fact that the little boy Hutchison picks up the first stone (in an effort to kill his mother!), the waiting until the last 2 paragraphs of the story to reveal the effect of the lottery and Old Man Warner's assertions that it has to be done even though other towns are considering doing away with it all contribute to the author's message of the absurdity of going through with things simply because we've done them before.

Examples of description in "The Lottery" that deepen the meaning of the text include the images that Jackson creates of the key items used in the actual lottery.  At the beginning of the story, the narrator describes the pile of stones that the children are building which at the end of the story is obviously crucial.  The descriptions of the black box, the black dotted papers, the characters of Mr. Summers and Mr. Graves, and the reactions of the neighbors to Tessie's arriving late to the lottery are all just as crucial and deepen the meaning of the story.  All are related to the symbolism surrounding the nature of blind tradition and rituals in which people participate.