If you're taking the pledge to not shop at major corporations that are on Santa's naughty list, be aware it's easy to accidentally buy from them if you buy things on eBay or other marketplaces.
It's common for people to list Amazon products on eBay under their own store. When you buy it, they simply use their Prime account to drop ship the item to your door with fast Prime delivery. If you've ever made a purchase on eBay and were surprised to see an Amazon delivery van pull up, you were actually buying from Amazon and paying some rando to borrow their Amazon Prime account.