I see so many services offering to double, triple and multiple in all possible amounts the coins you put to them. This doesn't sound very convincing to me but some of them are offering the list of blockchain transactions as a proof that coins were credited. Is this pure scam like I think or is there a possibility to realy make some coins? Would like to hear your thoughts and experiences.
Yes it is a pure Ponzi/ scam, It is actually has been scattered in the social media like on Facebook nowadays. And many of them are being victimize and no one is experiencing the ROI is giving back to them. Even they show some records in the blockchain it is a false record only, though they know most of the people in the social media are lack of knowledge in bitcoin so the scammer are too happy. That was a very sad part.