If this is about 1000 blockreward all the time it is strange.
Open the blocks and you'll see it's truly the blockreward (with sometimes the tiny fees).
Balance 137000.50700000
It is automated transactionscript or something? He transfers tiny bits all the time, nothing to do with blockfind, I suppose. This address is associated with a tradingrobot script maybe?
Likely a script, that monitors the diff and maybe renting power on Nicehash. I see on Nicehash a script execute pending orders (17GH) at the lowest price.