Changes to cart.items results in unwanted class/functionality duplication

I am modifying the markup created with rv-each-item="cart.items", adding a class and extra on click to one line item after event "cart.requestComplete" fires.  Which works fine, but as soon as I remove an item or add a new item from the cart page, that class and new onClick gets duplicated on the the new line item. I don't see why this would happen or the purpose for this, so it seems like a bug.