It is not a "lag" binance and bitstamp has always putted different prices on their exchanges, and they usually have the price of alts maybe less than five percent below of the real price on Bittrex or Poloniex, or just in coinmarketcap.
Binance has this ''problem'' a lot of times too, it usually lags several minutes behind other exchanges.
You can still make a lot of money if you have a good amount of money and you decide to do arbitrage in both exchanges, bithumb is a little bit risky because a lot of people had issues while they wanted to withdraw their money.
But in the other exchanges, you have a difference of three to four cents.
