I'm not worried, I just ask the question. I find it odd that there is such a "pro"attitude towards the blockchain, with no discussion about negative use cases. I think that kind of debate is healthy but it would be passed off as "FUD". The system is benign now but what will it evolve into? That is anyones guess. To think the blockchain will stay open source, in the hands of the the public is naieve. Especially when big money players come into the space like Google, etc. Anyway, I find it interesting and exciting to watch, not worrisome.