Regardless where one lives in Europe (including countries where salaries are lower than those living in France or Germany for example: such as Hungary, Romania, Latvia or Serbia to name a few) yet they’re confronted with 89,99€ at release considering EVERYONE in Europe as wealthy (further from the truth since there are nations in Europe where people aren’t paid 8000€ a month, some are paid x10 less than that).
Regional pricing is indifferent in this case no matter as to their actual income, it’s weird since they count countries where Euros aren’t used (Czech Republic, Romania, Serbia) whilst people there aren’t earning high salaries, like this: a Romanian earns 815€ a month but are treated no different: a 90€ game at launch (about 10% of their wage), for some reason they don’t bother adjusting it based on a specific country.
Directly in Steam it’s not that easy, you need a billing address and Steam checks the payment method to verify the country (although I don’t know if certain prepaid cards work for this as well).
You still have Steam keys, that can be sold anywhere though, and not everyone will care that this cheap key, intended for the Polish market is bought by someone in Germany.
Prepaid cards have to be loaded with a specific currency and usually are part of a pre-existing payment processor (VISA/Mastercard in the US).
Valve’s steam gift cards are sold in the same currency as well, and are usually usable for accounts in the same country of origin (read the back fine print)
I was thinking more along the line of PaysafeCard or things like that, although that might have similar currency restrictions. Or of course you can just buy foreign prepaid cards from third-party resellers. You’ll pay more than the card is actually worth, but if you would then be able to buy games for half price or even less, it would be worth it.