Why is the diff in BTC/USD rate larger than usual between Bitstamp (ChartBuddy) and Binance?

I check Binance rate in parallel mainly because they have bigger volume (not because I'm invested there).

Was thinking first if Binance is going "gox" with limitations in withdrawals or similar problem, or perhaps it's just less arbitrage going on. I already checked USDT and it doesn't diff much from USD at the moment.