The price of any cryptocurrency on exchanges can be different and sometimes these differences can be large whereas with other times it can be much smaller. This was something that i had noticed when it came to actually seeing the price of dogecoin increase, as the binance platform at one point had a much higher price than the yobit exchange platform. Have you ever tried trading between platforms like this and has it been successful? The withdrawal fees often play a large role in determining profitability of such ventures in my past experience.