To block the malware domains of coin-hive.
We think that using a javascript bitcoin miner on your site is malware. webmasters will and are abusing it, running it in the background without any the user knowledge.
For example, The pirate bay was using the bitcoin miner on the search list page. without ANY of the user knowledge. they stated that they're testing it. alot of the administrators didn't like it.
We suggest to stop using that and add a donation button / ads on your site instead.