TD Waterhouse works the same way. I was actually surprised at how little information was asked of me when I phoned in.
http://en.wikipedia.org/wiki/Automatic_number_identification
In an unrelated incident, I was talking to T-Mobile when the phone got cut off. They called me back (which was amazing customer service) until the first thing he said was he needed to authenticate I was me. So I was supposed to give him the last four digits of my social. I tried to reason with him why it was a bad idea but ended up thanking him and telling him that I'd call in at a later time.
Source: I work in VoIP, handle hundreds of thousands of 1-800 numbers on my network, as well as a lot of calls to toll-free numbers.