They’re not even the same currency at all, yet Steam or any other digital storefront decides to price a 80€ ($91) game the same as a $80 (69€) one when the conversions in reality are different to what the algorithm suggests. It’s reflected on Steam DB that Euro has a higher markup in comparison to US Dollar because of this, since I hear EU players nagging about paying 80€ at launch the same as US players don’t like paying $80.
But for physical goods, the minimum price is what the store paid for acquiring or producing it in the first place. That isn’t a consideration for digital goods.
Its less of a consideration, I would say the cost of selling a disc based game is not a hugely different cost to selling a digital game for major players in the industry