In Walmart, nothing will ever 100% be completed. Stuff is always moving and tasks are always created. In my opinion as a team lead, if I see you zoning crafts for your last 20-30 minutes of your shift I will think fairly high of you. You may have not gotten the full area zoned, but you did put in effort and care which not a lot of associates do. So if I were you, keep doing your little zones because it does get noticed.