No.
I am not mining at GHash.io, but they haven't done anything wrong.
Don't get me wrong. I would prefer the hashing power to be decentralized.
But, this is like worrying about Walmart destroying the US economy by not opening their doors on Monday. Yes, a few board members and a CEO could seriously damage the US economy - and by extension other economies to the tune of trillions of dollars. But, why? It would also destroy their own company.
Similarly, GHash.io, or any other large mining pool could cause trouble, but it would instantly destroy their company. They do not own 51%+ of the hashing power, they've attracted 51%+ of the decentralized hashing power to go through a centralized pool. That would end the instant they use their influence for evil.
lol
Mine and then vote here coinev.com/polls