Re: 27,000 litres of water used to make 1kg of chocolate
It makes a form of economic sense. If you could use that 27,000 litres more efficiently, why not? And that's completely correct. But for the fact the greenies depart from everyone else on the definition of efficiency, because they believe the resources of nature to belong to them rather than to all of us, and particularly those that own the land on which such resources fall.
Chocolate is an extravagant luxury that should be available in consequently limited quantities. Ideally it should only be served in first class at 35,000 feet, whence the organically-grown (or even better, wild-harvested) product can comfortably be purchased for a "fair trade" price from approved plantations, to airline customers on the way to the latest UN conference on carbon emissions from the aviation industry.
It is not something that can be efficiently left to the evils of the market for the producers to decide that's the best use of their resources rather than maize or subsistence farming, and for the plebeian customer to enjoy at €1 per 100 g bar. That is an inefficient use of the producer's resources and the consumer's money.