Upbit has taken the same approach at HitBTC, basically a small circle were just dumping and withdrawing BTC which wasn't beneficial to the end users and the exchange.
SBD still attracts good volume, hence the reason why it is still traded. The stakeholders have to take responsibility for this, its really just Bittrex left, everyone else has been the problem of a select few benefiting off the backs of many. Lets hope that things change around, I suspect they would remain in this mode until the situation changes