You're not even using a ZeusPay LN address. Most people who will Zeus on nostr the way you described in your OP will use a ZeusPay address set up within the Zeus app using their Olympus LSP and will incur those fees. 

https://image.nostr.build/5a0c51f8e93dbfabcfd6cc1982ccabda3a61750b3e20c4c272156df746811975.jpg