There are many online wallets like Xapo and Coinbase that do not charge any transaction fees or they pay that fees by themselves. I want to know that how would they profit from paying for their user's transaction fees ?
If no fees is charged then the transaction take a much long time or even might get cancelled !
I'm sure bitcoin online wallet are is not small company,they have good marketing plan and have great profit management,i think they earn profit from transaction fee,not witdraw fee,its why they have bitcoin exchange and market,and also they join with some others company to advertise and promotion.