Remove Grades from Sealed Pokemon Boxes. No grading companies grades boxes at this time

When I look for the value of a Pokemon box that contains a Promo almost all the eBay listings are for the graded promo card and not the sealed box. The Promo has its’ own listing in the Promo section on your site but most of the eBay listings are connecting to the sealed box and not to the promo card. This is skewing the price of the sealed box tremendously. Since none of the companies grade sealed boxes why do the sealed boxes have graded values?