maybe the dollar is more famous than the euro, I see the crypto trade financial system using dollar money as the main price indicator, I don't know why the dollar is highly prioritized in the financial system, but I feel strange, because the price of euros is more expensive than dollar .
Price of each nationalized currency depends upon the economy of the specific country. Euros has a bit higher price than dollars perhaps because of the centralized stock markets ruling over the centralized currencies.
Dollars make it easy of convenient trades and also dollars are been used in most of the online activities including major transactions. Whereas we can only use euros online at any specific local site which might be accepting euros. Dollars are turning dominant all over the other currencies and that's why even the decentralized markets have accepted dollars as a major mean of pair along with each major crypto-coin.