It is not worthy to use them. You would win only a dust amount saving them from the fees being paid by XAPO as an online web wallet provider but on the other side you risk your account to get blocked for different reasons and your bitcoins to remain locked there forever. It has happened to many people here in the forum so it is better to pay the fees and have a wallet which you are in control of everything.
yah youre right, better prioritize your bitcoins security in every situation. although i think only newbies will take advantage on this no miner fees thing that xapo offers when you
send a xapo to xapo transaction besides most newbies use online wallets. the situation is different now, with the high miner fees no wallet provider will shoulder any transactions
fees of their users. both xapo and coinbase offers that back then but they stopped. right now only internal transactions are with no miner fee. and i think with xapos increasing
bad reputation, the time will come when it'll stoop to coinbase level