Of course it does, everything in this world can be use in any illegal activities, even FIAT money used to illegal activities, how much more cryptocurrencies that is use in a virtual world and you are transacting to a person that you can't even see or touch that can make himself/herself fully anonymous in the internet, that is more far dangerous though.
And upon using bitcoin with illegal activities, those criminals are very favored for adopting it with their transactions for they will be hard to be traced.
Also they don't have to put their names or any other information that will be able to know their identity.
So they are taking advantage of bitcoins for their illegal activities, the same thing on how they use it with fiat money.
