Earlier quoted context omitted.
Ouch the Bitcoin example is terrible and really detracts from your argument. Currently Bitcoin is sucking value away from real economic output in the form of energy (electricity), financial speculation, money laundering, and cybercrime.
Terrible? I'm sure free software was also considered terrible 15 years ago at Microsoft! In fact, more than terrible- it was perceived as a cancer! Linux was sucking value away from real research in the form of copyleft (lost IP rights), financial speculation (VA Linux IPO, etc), hacking and other forms of cybercrime (don't they show nmap in the Matrix?) But perceptions change. The only thing that doesn't change much…
If your conception of value to society is as simple as "people pay money for it", maybe you should reconsider what value means outside of a purely monetary lens.
So far, bitcoin is a much costlier way to transact compared to standard methods - both to the end user, and in terms of energy/resource costs of miners vs. a VISA server.
It probably has some value in a scenario where the government is an adversary. But the government can regulate and track Bitcoin just as well as dollars if they wish to, like they already do in the US by requiring BTC exchanges to collect users identity proofs.
The arguments about how bitcoin is the next big thing and we'll all look silly for laughing at it now are basically empty. I'm sure i will feel silly if it takes off somehow, but that tells me nothing about if/why it will take off. I'll look silly for laughing at ghosts or leprechauns if they turn out to be real too, so what?