I agree that it is very important for people to be able to conduct financial transactions without having to disclose them to third parties. It's also important for people to be able to use a mutually-agreed-upon trusted third party to mediate transactions where neither party knows the other's identity. But I'm much less convinced of the wisdom of enabling people to conduct financial transactions with no possibility of knowing who they are doing business with. That seems to me to be fraught with all manner of moral hazard.