When you go to your admin/catalog/Reward Points you will see your categories. Click the edit button on the right side of the category and Set Category Reward Point ratio: 0.0000 click enter. The category you edited will not have any Reward Points. This will not effect all categories unless you did it wrong in the first place. You don't have to click each product in that category just the category and it will not display for that category. Hope that helps.
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