4.20
In the demo, the "Gift wrapping" checkout attribute has "Shippable product required" selected. If you add a shippable product to the cart and select the gift wrapping, then the additional fee appears. If you then remove the shippable item from the cart, and add a non-shippable item to the cart (e.g. a downloadable product), then the fee still appears (and yet the checkout attribute dropdown no longer appears).
