I think I read somewhere that when you check-in on the app, you have to add a card on file for onboard spending/charges. Is this true? If so, will RC charge a “hold” fee to your card even if you don’t purchase anything onboard? Also, I heard that you can add cash instead of a card. Is this true? If so, how would I opt-out of adding my card during check-in and just add cash instead? Thank you! (First time cruiser!)