WTH 3% FEE?
look at this way....
They convert the coin on the fly for you.
Don't have to manage 99999 coin wallets on your own
Don't have to deal with the exchange market
Don't have to deal with the "fee" to transfer your coin to and from the market
I'm happy to pay the 3% to just get my money via paypal or one of the major coins without having to do anything!
That is really why I use it.
I sold 400.00 in BitCoin today. It cost me about 6.00 to transfer it from my wallet to the exchange and 15.95 to sell it on the exchange.
It is usually cheaper to just cash it out straight to my paypal.
A few months ago it would cost a dollar to send 50.00 with bitcoin. I couldn't send bitcoin 3 days ago because it was about 9.00 to do a transaction, 13.xx to send it priority. That is simply crazy. While the fees have dipped down a little, bitcoin is still expensive to send. Then bitcoin is slow as dirt. My last transaction took almost 3 days sending it with "normal" priority. I could have snail mailed it faster. Bitcoin has huge problems. It is no longer a currency. It is just a speculation for people that hope it goes up so they can make a few dollars.
If you are looking just to dump (which is why people use nicehash and winminer) compared to having to sell a coin on an exchange 3% isn't bad, and most of the time you come out ahead.