Want to buy EA key from PoE shop with VISA with USD, but it makes me buy with PLN

I'm from poland but my visa card is connected to wallet with different currencies including USD. I want to buy the EA at PoE site, and want to pay 30 USD, but before the transcation it changes it to PLN, with worse exchange rate. It's not a big difference but why it does that when other places where things cost USD take my USD instead of my PLN?

The change happens when I put my card info. Here is what changes (without my card info in the pictures of course). It's all in polish, but I guess it looks the same in english.