Why are discounts applied to extra products in the cart?
The app creates percentage discounts using the Shopify Discount system, so we are tied to the Shopify Discount system rules.
In particular, you can limit the products that are required to apply a discount but not their number so, if your customers increase the number of those products, they will get a discount for the extra products.
For example, let's say that we have a 10% discount on the following products:
If we bought them together, we will get our 10% discount, as you can see in the following screenshot:
However, if we increase the number of any of those products, the 10% discount will still be applied to the extra items:
Please be aware of this behavior before enabling the discount feature in your store, as this is how Shopify Discounts work and we cannot change that.