The lesson here is to withdraw funds from shady exchanges as you accumulate them. They probably wouldn't have noticed a 0.1 BTC daily withdrawal, but the 2.7 BTC transaction set off alarm bells.
But the more you have on the exchange, the more trades you can do, and the faster you make money.
It doesn't matter how fast you can make it if you can't withdraw it.
You're not making money if you're not able to withdraw it.
yes, not your keys not your coins
I thought it was odd that they were smart enough to exploit the bot, but not smart enough to retrieve the money. Most people would have tried to withdraw a bit by bit to prevent alarms from being raised.
I guess they never thought this would work so wildly well. They would have expected for the site admins to tweak the bot to prevent exploitation.
He might have not realized the extent of the fake volume. Could have assumed he was a vanishingly small fish whose tiny withdrawal would not be noticed in the noise of an exchange reportedly doing $100MM daily.
Perhaps Bertyar88 didn't believe they were breaking any rules, and fully expected to be able to withdraw the funds, regardless of what anyone knew.
Could he have also just spent the coins?
No, the lesson is "avoid shady business partners because otherwise you will get robbed."
I know nothing about these things, but I assume that he would have made a lot less if he were regularly withdrawing profits. Though I would want to at least be doing some withdrawal tests along the way.