Is all of this about currency exchange rates and buying Steam Wallet codes with cash from local game stores?
I couldn't find any stores in Croatia or Russia based on Steam's FAQ for store locations world wide. There are a number of WEB sites dedicated to helping you find the best exchange rate price for boxed and downloadable games based on exchange rates and Steam store locations in real time. A monthly subscription fee game price for a none USA resident will be at the mercy of the exchange rates against the US $1.00 rate. So it's possible the price you pay in cash at a store each month outside of the USA for your Steam Wallet may fluctuate a bit depending on currency rate fluctuations. If Steam is a voluntary marketplace and you are not being charged a monthly subscription fee for access and your Steam Wallet, it's not a bad market model. Reminds me a bit of facebook focused on games in some respects.
The EU, Briton and Ireland have stores to pay cash for Steam Wallet codes. As of now Eastern Europe the only countries are Bulgaria, Macedonia, Greece, and Romania. And as I pointed out, no stores in Croatia or Russia.
Steam Wallet Codes and Steam Gift Cards are sold all over the globe. You can buy them in thousands of retail stores or online shops using your local payment methods.
1 dollar for example costs 6,63 in Croatia as of today.
If someone is from Croatia he has to pay HRK99,45 for $15. Now if a person in USA earns $3000 and person in Croatia HRK3000. Person in Croatia pays 6 times more, they both pay $15, but the person in Croatia to buy the $15 needs to pay 99,45 of his currency.
Just saying things like they are......
Croatia is not yet on the Euro which is projected for 2019.
Gold per gram today:
EU - 35.87
US - 39.98
Cr - 264.80 HRK