It's not just the fees.

Their method of using odd and varied numbers of decimal points for different pairs, means that every account ends up with loads of unspendable and unwithdrawable dust.  

Every single account ever used for trading diverse pairs on that exchange, has probably left behind an average of $5-10 (guessing, based on my own old account there from years ago) of untradeable and unrecoverable dust.

A factor of at least 10x (probably more like 100x) dust generation compared to other exchanges.