They don't have partnerships with the retailers they have partnerships with the gift card providers who will provide gift cards for these retailers/brands.
so there is an additional mediator there? Not direct purchase?
Basically its a chance for Gift card suppliers to sell their gift cards for crypto [ therefore entering another market] and for you the customer to purchase with crypto with no fiat or fees involved. So, for instance, Zeex's sister site Zeek will have there 450+ gift cards available on the app to buy with crypto.
You can see the app in action here https://www.youtube.com/watch?v=uE8CNBhS8Hg
I wish Zeex would eventually find a way to bypass the giftcard system and enable direct payments for goods.