No and Yes. "We will receive SEPA transfers in EUR and will convert them to USD according to our bank exchange rates."
Bitstamp trades pair BTC/USD. Not pair BTC/EUR.
You can swith to BTC/EUR.

of course, that is simple math. But the trades are i USD. BTW, we have in Europe not only euro. Euro is miserable currency.
as far as I know you can trade $ AND . the market is not really deep and it is hard to get larger orders through. it is separate from the $ marketplace