Ima be blunt, based on the fact that loads of people are still without exchanging trade pairs because the likes of binance and such have decided to close deposits indefinitely (gcse computer science and business for us teaches how to develop disaster recovery regimes) so the fact that high profit exchanges can't do it is just off.

Most of these exchanges do stuff with customers money too while on there especially if they haven't withdrawn for a long time. Coinbase, poloniex, bitmex and binance I believe will all be susceptible to this, as well as bitfinex who have already proven how great their money management strategies are (I luckily only had a dollar on there at the time of that hack)...