Let customers quick add a number of certain product quantity to get discount.
If the product has variants, the selected variants will be added in bulk when customers select the 'Add to cart' button in the feature.
The discount will still be applied if customers select a total of certain (tier's min quantity) product variants of the same item and add to cart manually.
In Cards layout, you can hide the 'Add to cart' button of the offer by selecting the corresponding option.
This allows you to use the theme's Add to cart button directly to add the targeted product in bulk .
Tip: In this case, you should hide the Quantity selector from your current product details as they now can select the quantity using Volume discount table.