Fees charged from the transactions are needed to support the networks that run the coin/token. This fee doesn’t go to us, it goes to reward miners (thereby ensuring that the transaction is logged into the blockchain in a timely fashion) and to support the Ethereum network itself.
As the new coins are implemented, each coin is a subject to its own transaction fee that is paid to their respected networks.
The fee amount depends on the level of difficulty of the transaction and the current network load. Please remember that higher fees guarantee faster confirmations. If there are a lot of transactions, miners process more expensive transactions first, and only after that they get to the cheaper ones.
You can always see the estimated fee when you enter the transaction amount. This is the fee that will be deducted from the sum you are about to send.
Also, please note that off-chain transactions between Freewallet customers are free of charge!