Are you serious? Of course there is action to be taken and it should have been reported to all customers of the security breech so that they can make up their minds if any action is to be taken not the company that has a duty of care to keep customers card and account details safe.
Have you ever had a card cloned or any fraud done with one of your cards. It is not as easy as saying to the bank "deal with this". How do you pay your rent or bills if the money/account has been frozen or the card cancelled? Even if the bank do handle it, there is always some issues, holdup or aggravate on that can cause all sorts of other problems.
There are a lot of people that do not have their bank account window open on their pc all the time to see every single transaction that goes through the account. It only takes a couple of days for several transactions to be made that could total thousands.. But yeah, the bank pays you back so its alright...
At the end of the day when the breech was detected and reported ALL customers using the service should have been informed by email or letter as a courtesy to inform PAYING CUSTOMERS that there is a possible issue and it would be prudent to check your account and get your card replaced. Handling it how they have done was utterly terrible and screams of "Lets not tell anyone, its not our fault and the bank will pay people back" in an attempt not to lose custom. But what it does do is incite distrust in a company and if that has an effect on business then it will be down to the way that they have handled it.