Patrick Frater Asia Bureau ChiefMildly titillating romantic comedy “Big Red Envelope” topped the box office rankings in China as overall takings in the world’s biggest theatrical movie market amounted to a lowly $37.5 million over the weekend.The new release title may be intended as a critique of obsessions with money, gifting culture and societal status – red packets are gifts of money in Chinese culture, given especially, but not exclusively, at Chinese New Year – but chunks of the audience