Not very. Being eco-friendly is one thing, being sustainable is another. Though both are attainable, for someone to be 100% sustainable in this day and age is rare. If I were 100% completely sustainable I wouldn't own a trash can or recycle bin, everything I owned would be reusable. I would only buy foods in bulk, not own any paper products, not drive a car but bike/walk everywhere, I wouldn't own little casualties like toasters or printers (products like these are made to expire, so people will throw them "away" and buy more. Plus the ink in printers is toxic to the environment... and I wouldn't have paper anyway). If I needed produce I'd go to the nearest local farm to get fruits and veggies (the fruit at the supermarket is sprayed with pesticides and the transportation to and from the farm released CO2). I could go on and on. Its defiantly more do-able to be eco-friendly, which still decreases the carbon footprint. I hope that one day we can all be sustainable, but for that to happen, food companies, product suppliers, architects and manufacturers need to be on the same boat. Did that help?? Oh yeah, if you haven't already, read Cradle to Cradle by William McDonough and Michael Braungart! It's a great book and will definitely help more with your question.