In this article, food and drink firms are called on to minimize their suppliers’ land grabbing. In light of the increasing demand for sugar by major food and Drinks companies like Coca Cola and PepsiCo among others, the source of this sugar has been pinpointed to cause problems in society. According to the report by Oxfam, (an international organization fighting poverty and injustice) sugar, soy and palm oil, are major causes of the large-scale land conflicts.
This is an ethical question on how much businesses should ensure that they undertake their transactions in a fair manner. However, is it their responsibility not to buy sugar until they have all the precise details of how their suppliers affect the society or any other parties? And how far are they expected to scrutinize the activities of their suppliers?
I agree they have a responsibility to ensure their activities have a positive impact on the environment and the society. However, extending their role to that of managing their partners is completely piling an extra role for them, which they do not deserve.

http://www.theguardian.com/global-development/2013/oct/02/sugar-food-drink-land-grabs