This is a very serious issue and I am very sorry for your friend's loss. Thank you for writing this though as it will serve as a very important reminder not to give out private informations lightly.
I have had a bank call me once to ask me to deposit RM3000 into my savings account to gain more interests. Though it was not a scam, it was a promotional offer, I had to practise precaution so as to make sure that they knew who they were calling instead of just randomly selecting "victims"
Great Reminder!
Yep, better safe than sorry I say. All it takes is a slip of the tongue or a careless mistake and one could give away a lot more than one bargained for.