Razer Hammerhead pro v2 Question

Hello everyone i am a new member in your forum and i got a question.I bought my first razer product almost a year ago (i think) it was and still is the razer hammerhead pro v2.I am totally satisfied with the product and i promote it to all my friends.I got 0 problems with it and i use it every day.But my question is this,why does it cost in my country 60 euros (almost) and on some chinese internet sites it costs 20 dollars or about 17 euros?A guy from my country wrote a message asking whether or not his pair of razer hammerhead pro v2's that he bought,was genuine or not (he bough it for 17 euros from a chinese site).Later he asked the support and they told him they are genuine.Why is this happening?And i dont want to promote other sites but from the razer's site ,this particular site wasnt on the official sellers.My first thought was that he bought fake earphones.Can someone tell me why is this happening?I have also encaountered it with razer deathadder mouse in a chinese store again,the code worked.Thank you for your time and i am sorry for my english i am not a native speaker.