This village hasn't given up on the practice of the lottery because it has always been done. This story's purpose is to illustrate the ineffectiveness of some of life's traditions. This village blindly continues the lottery for no apparent reason.
Old Man Warner notes:
"Nothing but trouble in that," Old Man Warner said stoutly. "Pack of young fools."
Here he is referencing the fact that other towns are giving it up because new generations do not think it is relevant anymore. In this town, there is still enough influence by Mr. Summers, Mr. Graves and Old Man Warner to continue the tradition for tradition's sake. Warner says there is trouble in giving up the lottery, but the town has never tried so they don't know what the trouble might be. Another reason for not giving up the lottery may have to do with the fear of the unknown.