"Most of the prices in electrical stores end in.99p. But a few end in.98p or 95p. That's a signal that a product is old stock and needs to be sold quickly. If you're foolish enough to ask a sales assistant for advice in a big electrical chain, the loyal staff will steer you towards these." [mefi]
This type of deliberate steering is documented in a this American Life story I heard recently (11/19/04: Episode 278: "Act Three. Mystery Shoppers. They are ordinary people who go undercover in coffee shops and chain stores, spying for The Man. " ) The Mystery shoppers would judge whether the saleshelp were "on script" and plugging the right product that was designated to move that day.