I believe just the same way people got hive to power up, so did some people get hive to sell off. A lot of account that knew they would not get the airdrop could send tokens to exchanges thereby getting the token via the medium. What happens then is that people start to sell off their hive to wager steem. As much funds are being pulled out in millons in regards of steem, the price tends to be relatively stable or just experienced a little drop in price.