Omg this guy is an idiot. I wish I had that many bitcoin's, if I did I certainly wouldn't be so stupid with them. I hope the sender gets them back but I doubt it.
This guy is super smart, 2 words: money laundering, I am pretty sure the right guy got thoose fees.
If this is money laundering then how did it work. Here is how to launder money. You give me 300 bitcoins. I tell the IRS that I made those bitcoins selling lemonade. I give you back 280 bitcoins that I made selling lemonade and tell the government that you sold me lemons. The key to money laundering is a believable lemonade business and lies.
Where are the believable income stream in this big fee laundry? The bitcoins don't look the least bit washed.
Mining farm > lemonade business
You earned that fee fair and square. You even agreed to return it as a good gesture, but no one claimed it. No it's yours, you pay tax on that profit and enjoy spending. Much better than lemonade business, you don't have to fake any invoices to prove that there were actual lemons involved.
Only works if operator of mining farm or pool is entitled to keep the entire fee or significant portion of it (doesn't have to share with other miners).