Reuters: Retailers, seeking to cut costs in the economic downturn, need to continue investing in environmental sustainability if they want to retain customers, according to a report published on Wednesday. Havas Media, opening the annual World Retail Congress, said a survey of 20,000 consumers in 10 countries found that 80 percent would reward brands that adopted sustainable practices, while 72 percent would punish those that did not. Some 48 percent of the people surveyed also said …