The only thing that make us bitcoin enthusiasts bad is by those criminals using bitcoin in deep web for illegal transactions like selling drugs, selling illegal fire arms and other stuff but they other police did not know that majority of the bitcoin enthusiast use it for good things like making it a part time job to earn some money from trading and investment sites.
How do you know "majority of the bitcoin enthusiast use it for good things". There is pretty much no market in the world that exclusively caters to Bitcoin users other than the dark web and Silk Road type sites. If I were going to take a wild guess (which is what you did) I would guess that a few people are using it for legitimate purposes like investments and the bulk are using it for illegal purposes.
True, not all users of the bitcoin use it for things that are bad (Mafia, Illegal Commercial, illegal, and dangerous). I also think that those who say that Bitcoin users always doing dangerous deals, it is the people who have eaten or Violent movies too often or perhaps he feared innovations!