The ethical consumerism means the intentional buying behavior of consumers from their ethical motive. The current ethical consumerism started in the 1980s in the UK.
As for the reason why consumers prefer goods which are made ethically in spite of relatively high price compared to conventional goods, I suppose two key ideas which underpin consumer’s ethical purchase. One is the concept of ‘commitment’ by A.K.Sen, the other is ‘ethical preference’ by M.K.Gandhi.
The Korean consumer co-ops have developed ethical consumerism, too. For expanding ethical consumerism in Korea, they would try to encourage small business actors in local market.