Customers play a critical role in implementing the "sustainable green" concept in supply chains through their activism. By refusing to buy from companies that act irresponsibly, consumers put pressure on their suppliers to move towards sustainability. A recent great example of this is how, in response to their customers' health concerns, McDonald's has agreed to phase out the use of antibiotics in raising its poultry. 

When you speak of sustainable green concept applied in Supply Chains I think directly in Reverse Logistics. On that context, customers are critical since they must behave different to what non-green companies offer as service. For instance, beverage companies modifying their SC to receive back the empty bottles rely on customers' activism as Kalyan  already mentioned. Otherwise they wouldn't be profitable after such a huge investments in facilities' redesign.

I thank all respected professors and researchers for their valuable answers and recommendations.

Thank you Professor Dubey for putting more light on this relevant issue in today's context. Regards.