When the Fry's Electronics in Indiana opened years ago, they staffed one person per aisle, and even put a polaroid picture of them on the end of the aisle (in case you couldn't pick out the person in a white shirt and black pants). I don't think that staffing model lasted a year for them here, and having never been to a West Coast Fry's, I don't know if it was something they attempted here or the norm. But, in the case of other retailers (one of whom I work for), it is definitely not the norm in the US market, and is usually more like one or two per department, not aisle.