Are you sure? I read the fine print and I don't think they are excluded this time.
The email I received had this in the fine print:
"Qualifying purchase based on pre-tax, post-discount amount
and excludes shipping and handling charges, gift cards, gift wrap and gift boxes, publications, memberships, media, games and accessories, electronics, Disney INFINITY, Disney Theme Park passes, Limited Edition merchandise,
Dooney & Bourke, Duffy the Disney Bear Collection, select Monsters University Campus Store merchandise, Monstrous Summer Tee, personalization, and items not in stock."
I also just tried to use the code on a bag, and it said the code was invalid.
They are rarely discounted online anymore, except for Disney Visa cardholders and DVC members. Like someone else mentioned above, you can sometimes find a 20% off coupon on counter service receipts that can be used on property, as well as annual pass discounts.