It depends on context. In a situation where bargaining over price is the norm, failing to do so is foolish and the person selling the item will be pleased to rip you off. In a situation where prices are fixed, if you attempt to bargain you will be perceived very negatively and in some cases, you may be violating criminal laws (e.g. trying to bargain with a transit driver over fares, or trying to cut a deal with a policeman giving you a ticket).
