The price is not 1 dollar because it is traded on these exchanges. But I think that the reason for the high price is that too few SBD is created. If more SBD would be created the price would drop. The price of SBD was 1 dollar for a very long time, but from the point when Steem was 'hyped' it started to rise. But I don't know, maybe there are other reasons for the price to be over 1 dollar.