Guardian: Supermarket giant Sainsbury’s is to roll out “eco-friendly” milk bags and jugs across its entire product range in a multi-million pound move to reduce the carbon footprint of milk consumption. In partnership with supplier Dairy Crest, Sainsbury’s is putting its full marketing weight behind the product, confident that reluctant consumers now understand how to use it after a series of technical modifications and an education programme. The push comes despite the failure of a similar …