Our current dietary habits are a major contributor to climate change because the “seed-to-table” food chain produces an immense amount of greenhouse gases (GHGs) (Castellón et al., 2015). For instance, in Spain, the agricultural sector contributes 14% of the country’s total greenhouse gas (GHG) emissions (Bourne et al., 2012). Hedenus et al. (2014) showed that emission reduction in the agro-food sector can be achieved by: (1) productivity improvements; (2) technological changes (supply-side measures); and (3) changes in consumption behaviour (demand-side measures). Supply side measures such as command-and-control regulations, cap-and-trade systems or Pigovian (corrective) taxes, have been applied extensively in the European Union (Máca et al., 2012). However, the use of command–and-control measures has been found to be economically inefficient and does not lead to optimal production, when compared to cap-and-trade measures or Pigovian taxes (Burchell and Lightfoot, 2001).