Maybe zeex aims at removing those 3% that credit cards companies take? As I'm not sure what can be done for Amazon share.
But they will charge a fee, won't they?
As a user, the only fees you will experience are network fees related to the execution of the smart contract (aka gas), Zeex itself does not charge any fee for conversion.

For more, see Medium Article:
"Zeex Crypto to Products no Fiat, no Fees!"
https://medium.com/the-zeex-protocol/zeex-crypto-to-product-no-fiat-no-fees-872602f1faa3