I got sacked from HMV because I said on facebook that "I need a new job."
My facebook profile is private, always has been, and someone basically told my boss and had shown them my profile via his own.
It was a pretty rubbish place to work for. There's a huge pressure to sell those HMV Pure cards which aren't very good and price at £3. They'd be good if they were free, a la the Tesco club card or any other kind of store discount card, but it's difficult to sell someone something that means you have to spend at least £1000 in the space of six months in order to get any off the decent "special stuff" they have on offer.
Oh, and the points get erased after 6 months. So it's a bit of a cop out, really.
People can be decent though, and like any store job you restock etc which is dull but tolerable.