It's not just old folks. I just returned from a week of training. One of my class mates got a call from "the front desk" saying there was something wrong with his credit card. They asked for his information and said he could pick up a receipt when he was leaving. You know what happens when he got to the front desk. It wasn't the hotel calling.
Never give information over the phone if you did not initiate the call.
Never give information over the phone if you did not initiate the call.