I rarely pre-wash--I rub a white paper hard on any fabric that is a deep color (darks, batiks, etc) and if any color shows then it does get pre-washed, otherwise it's not prewashed. I like the fabric to have some sizing when I cut and sew it. I do attach wash/dry instructions to all quilts that I gift--and part of that includes throwing in a couple of color catchers--which I do every time I wash a quilt. The one exception is with a child's quilt, which I do wash out.
I know others will saw that's gross that it's not washed before gifting--but when we buy a bed spread, does it get washed first?