The digital rub-ons in our shop are the digital equivalent of the popular traditional rub-ons you might have purchased at a craft store.
Instead of having to rub them on with a lollipop stick, you just open them and drag them onto your layout using a graphics editing program like Photoshop, Photoshop Elements, Paint Shop Pro, etc.
They are applied to a digital page the same way you apply digital stickers, elements and overlays.
They are simply meant to simulate rub-ons on a digital scrapbook page or other digital project. Because they are meant to look like they are stuck on the surface of your scrapbook page, you won't want to apply a drop-shadow to them like you might with other embellishments.