Hi Kristen,
Thank you so much for visiting the Disney Parks Moms Panel with your question. We on the panel love helping guests to plan magical vacations!
Taking advantage of some shopping discounts while you are at Walt Disney World is a great idea. There are so many
merchandise locations throughout Walt Disney World with a variety of items for every guest. I love finding unique items to bring home to remember my trips. I search each trip for a special shirt or purse to purchase. I also have quite a collection of Mickey Mouse earrings!
I suggest that you visit www.disneydebit.com. From there, choose "Vacation Perks" and then "Walt Disney World." If you scroll down, you will see that there is a section about merchandise, and you are correct at 10% discount is offered "at select locations." There is a corresponding footnote with more information - it is footnote number three. There you will find some details on the offer including minimum purchase and exclusions for this offer.
I find that the best course of action when trying to determine if a certain location offers a discount is simply to ask a cast member working at that location. They will let you know if your discount is available at that location.
I hope that these thoughts are helpful for you, Kristen! Please do let us know if you have any further questions.