How To Change The Credit Card Used For An Existing Reservation?

I made several reservations in Europe (Spain and Italy) using a credit card that has been recently used for fraudulent activity. The bank cancelled the card and issued a new one. However, some hotels are contacting me warning that they need the new information in order to secure the reservations. I am already on the go and I am afraid of sending the credit card info by email. What should I do? Should not be enough to wait until check-in day and present the new card? Why do hotels check in advance if the cc works? Thanks!