I once had a weird interview at an investment bank for a backroom sysadmin position. I went to the interview in a smart cotton tennis shirt, black trousers, and was interviewed by a bunch of techie people wearing pretty much the same kind of clothes. The interview covered many technical issues and seemed to go really well.
When I got out and was on my way home, the recruitment consultant phoned me up and quite literally screamed at me for about 5 minutes down the phone about why I hadn't worn a suit. He didn't mention this interview requirement beforehand.
So yeah, weird things happen at investment banks :-) I didn't get the job obviously.
For one of my first job interviews I called to company whether they wore suits. They said yes. I bought a suit and got a haircut, and was interviewed by two techies in smudgy polo and sweater. I felt way overdressed, didn't get hired, and decided to never do this again. A neat button-down shirt is plenty.
When I got out and was on my way home, the recruitment consultant phoned me up and quite literally screamed at me for about 5 minutes down the phone about why I hadn't worn a suit. He didn't mention this interview requirement beforehand.
So yeah, weird things happen at investment banks :-) I didn't get the job obviously.