Confirming identity

"Hi, I'm calling from the water company. May I speak to Kitt?"

"This is she."

"Hi. To confirm identity, could I have your date of birth?"

"Absolutely not. You called me. I have no way of verifying who you are."

"I'm from the water company. I need your date of birth to confirm who I am talking to."

"That's nice, but I don't know who you are, so no. What's this about?"

"I can't say until I confirm I'm talking to Kitt."

"Okay."

*click*

...

WTF? Seriously? Does that work with other people? Hi, let me give my personal information out to any caller? It's not like finding my date of birth is difficult, so using it as a way of confirming identity has to be one of the dumbest ideas ever.