First I was also compelled to ask this . But the thing with steem is it incentivizes contents and stories being written . I for one love writing articles and want to have rewards for it. But being classified as decentralized social media make steem more appealing to the people where they can really interact or say their things . By contributing such articles and getting involved make the Steem network run is a proof of work that needs more and more participants as time goes by.