As I said in a previous post, you may be somewhere where they don't take cards.  It happens at smaller places.  The thing is, you don't want to be stuck searching for cash or skip something you want to buy because they don't take cards.

Also, make sure you have some money in checking and savings for the ATM's.  The ATM's in both Switzerland and Rome that I used on my last trip didn't ask which account they cash was coming from.  Some were from savings and some were from checking.