I LOVE self checkout. Faster, and I don't have to deal with a possible moron (exceptions being Trader Joes and Costco). I figured when they were introduced the purpose was to get people used to the concept so the switch to automatic RFID checkout totals would have less resistance. Still waiting...
My experience was exactly the opposite. The employees only had to intervene when I was buying stuff that needed human interaction (alcohol and expensive items with these anti-theft thingies that have to be removed). Maybe it's just that self-checkout in USA sucks?