There are huge discrepancy and volatility in the SBD markets right now, as you can see in the market page here at https://www.coingecko.com/en/coins/steem-dollars#markets
To be honest, this is an edge case scenario, HitBTC's trading volume of SBD at $0.30+ matches the remaining exchanges which traded at $0.60+, and because of this SBD is both priced at $0.30+ and $0.60+ at the same time, since both are traded at that price in different markets. Our Trust Score algorithm ended up favoring HitBTC's data based on the metrics it has which is why we are showing $0.30+
How does it happen that there a 100% difference in price?
And why don't people trade that? They can really profit by finding a middle ground between 0,3 and 0,6