Your euro ATM card may work, depending what 'network' it cooperates with. Various bank ATMs may support different networks. Example: My STAR card works on PLUS networks. Worked fine in Mexico, works all across the USA at any STAR ATM or other ATM with a PLUS logo. Check the back of your card.
Credit cards are widely accepted everywhere, except possibly smaller 'mom & pop' operations. But most any national chain will take plastic, even McDonalds if you 'need' a Royale mit Kasse.
Oh, and based on what I experienced in Germany, a 'continental breakfast' at a hotel here in the USA will grossly disappoint you.
What bike are you bringing over?