Not to state the obvious, although apparently it must be done: companies, whatever benefit you get by taking advantage of a moment of misfortune through excessivepricing or tacky advertising is not worth the backlash you may be hit with in this era of instant communications and 24-hour news cycles.
With respect to fast moving consumer goods, excessive discounting (pricing too low) can effectively train consumers to look for a certain sale price and wait for that price before they buy.