Great tool, thanks for that! I just don't understand one thing, can you help please?

When I buy cheap on one exchange then I sell it on another exchange I make a profit. But I still have my money on that exchange, I don't have them actually on my credit card. When I want to send the money to my credit card, everywhere are fees like 2% or even more! So I don't understand how you can make money on it basically.

Can you explain please?